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600 lines
21 KiB
600 lines
21 KiB
#! /usr/bin/env python
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import random
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from optparse import OptionParser
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import string
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def tprint(str):
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print str
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def dprint(str):
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return
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def dospace(howmuch):
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for i in range(howmuch + 1):
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print '%28s' % ' ',
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# given list, pick random element and return it
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def pickrand(tlist):
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n = int(random.random() * len(tlist))
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p = tlist[n]
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return p
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# given number, conclude if nth bit is set
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def isset(num, index):
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mask = 1 << index
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return (num & mask) > 0
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# useful instead of assert
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def zassert(cond, str):
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if cond == False:
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print 'ABORT::', str
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exit(1)
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#
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# Which files are used in the simulation
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#
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# Not representing a realistic piece of anything
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# but rather just for convenience when generating
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# random traces ...
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#
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# Files are named 'a', 'b', etc. for ease of use
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# Could probably add a numeric aspect to allow
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# for more than 26 files but who cares
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#
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class files:
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def __init__(self, numfiles):
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self.numfiles = numfiles
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self.value = 0
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self.filelist = list(string.ascii_lowercase)[0:numfiles]
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def getfiles(self):
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return self.filelist
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def getvalue(self):
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rc = self.value
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self.value += 1
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return rc
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#
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# Models the actions of the AFS server
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#
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# The only real interactions are get/put
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# get() causes the server to track which files cache what;
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# put() may cause callbacks to invalidate client caches
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#
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class server:
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def __init__(self, files, solve, detail):
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self.files = files
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self.solve = solve
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self.detail = detail
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flist = self.files.getfiles()
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self.contents = {}
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for f in flist:
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v = self.files.getvalue()
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self.contents[f] = v
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self.getcnt, self.putcnt = 0, 0
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def stats(self):
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print 'Server -- Gets:%d Puts:%d' % (self.getcnt, self.putcnt)
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def filestats(self, printcontents):
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for fname in self.contents:
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if printcontents:
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print('file:%s contains:%d' % (fname, self.contents[fname]))
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else:
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print('file:%s contains:?' % fname)
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def setclients(self, clients):
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# need list of clients
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self.clients = clients
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# per client callback list
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self.cache = {}
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for c in self.clients:
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self.cache[c.getname()] = []
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def get(self, client, fname):
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zassert(fname in self.contents, 'server:get() -- file:%s not found on server' % fname)
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self.getcnt += 1
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if self.solve and isset(self.detail, 0):
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print('getfile:%s c:%s [%d]' % (fname, client, self.contents[fname]))
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if fname not in self.cache[client]:
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self.cache[client].append(fname)
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# dprint(' -> List for client %s' % client, ' is ', self.cache[client])
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return self.contents[fname]
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def put(self, client, fname, value):
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zassert(fname in self.contents, 'server:put() -- file:%s not found on server' % fname)
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self.putcnt += 1
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self.contents[fname] = value
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if self.solve and isset(self.detail, 0):
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print('putfile:%s c:%s [%s]' % (fname, client, self.contents[fname]))
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# scan others for callback
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for c in self.clients:
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cname = c.getname()
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if fname in self.cache[cname] and cname != client:
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if self.solve and isset(self.detail, 1):
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print 'callback: c:%s file:%s' % (cname, fname)
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c.invalidate(fname)
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self.cache[cname].remove(fname)
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#
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# Per-client file descriptors
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#
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# Would be useful if the simulation allowed more
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# than one active file open() at a time; it kind
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# of does but this isn't really utilized
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#
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class filedesc:
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def __init__(self, max=1024):
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self.max = max
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self.fd = {}
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for i in range(self.max):
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self.fd[i] = ''
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def alloc(self, fname, sfd=-1):
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if sfd != -1:
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zassert(self.fd[sfd] == '', 'filedesc:alloc() -- fd:%d already in use, cannot allocate' % sfd)
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self.fd[sfd] = fname
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return sfd
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else:
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for i in range(self.max):
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if self.fd[i] == '':
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self.fd[i] = fname
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return i
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return -1
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def lookup(self, sfd):
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zassert(i >= 0 and i < self.max, 'filedesc:lookup() -- file descriptor out of valid range (%d not between 0 and %d)' % (sfd, self.max))
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zassert(self.fd[sfd] != '', 'filedesc:lookup() -- fd:%d not in use, cannot lookup' % sfd)
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return self.fd[sfd]
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def free(self, i):
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zassert(i >= 0 and i < self.max, 'filedesc:free() -- file descriptor out of valid range (%d not between 0 and %d)' % (sfd, self.max))
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zassert(self.fd[sfd] != '', 'filedesc:free() -- fd:%d not in use, cannot free' % sfd)
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self.fd[i] = ''
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#
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# The client cache
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#
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# Just models what files are cached.
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# When a file is opened, its contents are fetched
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# from the server and put in the cache. At that point,
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# the cache contents are VALID, DIRTY/NOT (depending
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# on whether this is for reading or writing), and the
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# REFERENCE COUNT is set to 1. If multiple open's take
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# place on this file, REFERENCE COUNT will be updated
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# accordingly. VALID gets set to 0 if the cache is
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# invalidated by a callback; however, the contents
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# still might be used by a given client if the file
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# is already open. Note that a callback does NOT
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# prevent a client from overwriting an already opened file.
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#
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class cache:
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def __init__(self, name, num, solve, detail):
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self.name = name
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self.num = num
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self.solve = solve
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self.detail = detail
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self.cache = {}
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self.hitcnt = 0
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self.misscnt = 0
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self.invalidcnt = 0
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def stats(self):
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print ' Cache -- Hits:%d Misses:%d Invalidates:%d' % (self.hitcnt, self.misscnt, self.invalidcnt)
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def put(self, fname, data, dirty, refcnt):
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self.cache[fname] = dict(data=data, dirty=dirty, refcnt=refcnt, valid=True)
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def update(self, fname, data):
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self.cache[fname] = dict(data=data, dirty=True, refcnt=self.cache[fname]['refcnt'], valid=self.cache[fname]['valid'])
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def invalidate(self, fname):
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zassert(fname in self.cache, 'cache:invalidate() -- cannot invalidate file not in cache (%s)' % fname)
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self.invalidcnt += 1
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self.cache[fname] = dict(data=self.cache[fname]['data'], dirty=self.cache[fname]['dirty'],
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refcnt=self.cache[fname]['refcnt'], valid=False)
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if self.solve and isset(self.detail, 1):
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dospace(self.num)
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if isset(self.detail,3):
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print '%2s invalidate %s' % (self.name, fname)
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else:
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print 'invalidate %s' % (fname)
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self.printstate(self.num)
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def checkvalid(self, fname):
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zassert(fname in self.cache, 'cache:checkvalid() -- cannot checkvalid on file not in cache (%s)' % fname)
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if self.cache[fname]['valid'] == False and self.cache[fname]['refcnt'] == 0:
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del self.cache[fname]
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def printstate(self, fname):
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for fname in self.cache:
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data = self.cache[fname]['data']
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dirty = self.cache[fname]['dirty']
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refcnt = self.cache[fname]['refcnt']
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valid = self.cache[fname]['valid']
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if valid == True:
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validPrint = 1
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else:
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validPrint = 0
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if dirty == True:
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dirtyPrint = 1
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else:
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dirtyPrint = 0
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if self.solve and isset(self.detail, 2):
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dospace(self.num)
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if isset(self.detail, 3):
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print '%s [%s:%2d (v=%d,d=%d,r=%d)]' % (self.name, fname, data, validPrint, dirtyPrint, refcnt)
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else:
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print '[%s:%2d (v=%d,d=%d,r=%d)]' % (fname, data, validPrint, dirtyPrint, refcnt)
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def checkget(self, fname):
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if fname in self.cache:
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self.cache[fname] = dict(data=self.cache[fname]['data'], dirty=self.cache[fname]['dirty'],
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refcnt=self.cache[fname]['refcnt'], valid=self.cache[fname]['valid'])
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self.hitcnt += 1
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return (True, self.cache[fname])
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self.misscnt += 1
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return (False, -1)
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def get(self, fname):
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assert(fname in self.cache)
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return (True, self.cache[fname])
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def incref(self, fname):
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assert(fname in self.cache)
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self.cache[fname] = dict(data=self.cache[fname]['data'], dirty=self.cache[fname]['dirty'],
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refcnt=self.cache[fname]['refcnt'] + 1, valid=self.cache[fname]['valid'])
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def decref(self, fname):
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assert(fname in self.cache)
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self.cache[fname] = dict(data=self.cache[fname]['data'], dirty=self.cache[fname]['dirty'],
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refcnt=self.cache[fname]['refcnt'] - 1, valid=self.cache[fname]['valid'])
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def setdirty(self, fname, dirty):
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assert(fname in self.cache)
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self.cache[fname] = dict(data=self.cache[fname]['data'], dirty=dirty,
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refcnt=self.cache[fname]['refcnt'], valid=self.cache[fname]['valid'])
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def setclean(self, fname):
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assert(fname in self.cache)
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self.cache[fname] = dict(data=self.cache[fname]['data'], dirty=False,
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refcnt=self.cache[fname]['refcnt'], valid=self.cache[fname]['valid'])
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def isdirty(self, fname):
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assert(fname in self.cache)
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return (self.cache[fname]['dirty'] == True)
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def setvalid(self, fname):
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assert(fname in self.cache)
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self.cache[fname] = dict(data=self.cache[fname]['data'], dirty=self.cache[fname]['dirty'],
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refcnt=self.cache[fname]['refcnt'], valid=True)
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# actions
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MICRO_OPEN = 1
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MICRO_READ = 2
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MICRO_WRITE = 3
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MICRO_CLOSE = 4
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def op2name(op):
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if op == MICRO_OPEN:
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return 'MICRO_OPEN'
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elif op == MICRO_READ:
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return 'MICRO_READ'
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elif op == MICRO_WRITE:
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return 'MICRO_WRITE'
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elif op == MICRO_CLOSE:
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return 'MICRO_CLOSE'
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else:
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abort('error: bad op -> ' + op)
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#
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# Client class
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#
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# Models the behavior of each client in the system.
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#
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#
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#
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class client:
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def __init__(self, name, cid, server, files, bias, numsteps, actions, solve, detail):
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self.name = name # readable name of client
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self.cid = cid # client ID
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self.server = server # server object
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self.files = files # files object
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self.bias = bias # bias
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self.actions = actions # schedule exactly?
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self.solve = solve # show answers?
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self.detail = detail # how much of an answer to show
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# cache
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self.cache = cache(self.name, self.cid, self.solve, self.detail)
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# file desc
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self.fd = filedesc()
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# stats
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self.readcnt = 0
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self.writecnt = 0
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# init actions
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self.done = False # track state
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self.acnt = 0 # this is used when running
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self.acts = [] # this just tracks the opcodes
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if self.actions == '':
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# in case with no specific actions, generate one...
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for i in range(numsteps):
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fname = pickrand(self.files.getfiles())
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r = random.random()
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fd = self.fd.alloc(fname)
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zassert(fd >= 0, 'client:init() -- ran out of file descriptors, sorry!')
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if r < self.bias[0]:
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# FILE_READ
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self.acts.append((MICRO_OPEN, fname, fd))
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self.acts.append((MICRO_READ, fd))
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self.acts.append((MICRO_CLOSE, fd))
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else:
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# FILE_WRITE
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self.acts.append((MICRO_OPEN, fname, fd))
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self.acts.append((MICRO_WRITE, fd))
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self.acts.append((MICRO_CLOSE, fd))
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else:
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# in this case, unpack actions and make it happen
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# should look like this: "oa1:ra1:ca1" (open 'a' for reading with file desc 1, read from file a (fd:1), etc.)
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# yes the file descriptor and file name are redundant for read/write and close
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for a in self.actions.split(':'):
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act = a[0]
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if act == 'o':
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zassert(len(a) == 3, 'client:init() -- malformed open action (%s) should be oa1 or something like that' % a)
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fname, fd = a[1], int(a[2])
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self.fd.alloc(fname, fd)
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assert(fd >= 0)
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self.acts.append((MICRO_OPEN, fname, fd))
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elif act == 'r':
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zassert(len(a) == 2, 'client:init() -- malformed read action (%s) should be r1 or something like that' % a)
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fd = int(a[1])
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self.acts.append((MICRO_READ, fd))
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elif act == 'w':
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zassert(len(a) == 2, 'client:init() -- malformed write action (%s) should be w1 or something like that' % a)
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fd = int(a[1])
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self.acts.append((MICRO_WRITE, fd))
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elif act == 'c':
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zassert(len(a) == 2, 'client:init() -- malformed close action (%s) should be c1 or something like that' % a)
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fd = int(a[1])
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self.acts.append((MICRO_CLOSE, fd))
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else:
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print 'Unrecognized command: %s (from %s)' % (act, a)
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exit(1)
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# debug ACTS
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# print self.acts
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def getname(self):
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return self.name
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def stats(self):
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print '%s -- Reads:%d Writes:%d' % (self.name, self.readcnt, self.writecnt)
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self.cache.stats()
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def getfile(self, fname, dirty):
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(incache, item) = self.cache.checkget(fname)
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if incache == True and item['valid'] == 1:
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dprint(' -> CLIENT %s:: HAS LOCAL COPY of %s' % (self.name, fname))
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self.cache.setdirty(fname, dirty)
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else:
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data = self.server.get(self.name, fname)
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self.cache.put(fname, data, dirty, 0)
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self.cache.incref(fname)
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def putfile(self, fname, value):
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self.server.put(self.name, fname, value)
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self.cache.setclean(fname)
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self.cache.setvalid(fname)
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def invalidate(self, fname):
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self.cache.invalidate(fname)
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def step(self, space):
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if self.done == True:
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return -1
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if self.acnt == len(self.acts):
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self.done = True
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return 0
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# now figure out what to do and do it
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# action, fname, fd = self.acts[self.acnt]
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action = self.acts[self.acnt][0]
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# print ''
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# print '*************************'
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# print '%s ACTION -> %s' % (self.name, op2name(action))
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# print '*************************'
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# first, do spacing for command (below)
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dospace(space)
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if isset(self.detail, 3) == True:
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print self.name,
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# now handle the action
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if action == MICRO_OPEN:
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fname, fd = self.acts[self.acnt][1], self.acts[self.acnt][2]
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tprint('open:%s [fd:%d]' % (fname, fd))
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self.getfile(fname, dirty=False)
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elif action == MICRO_READ:
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fd = self.acts[self.acnt][1]
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fname = self.fd.lookup(fd)
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self.readcnt += 1
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incache, contents = self.cache.get(fname)
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assert(incache == True)
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if self.solve:
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tprint('read:%d -> %d' % (fd, contents['data']))
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else:
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tprint('read:%d -> value?' % (fd))
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elif action == MICRO_WRITE:
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fd = self.acts[self.acnt][1]
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fname = self.fd.lookup(fd)
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self.writecnt += 1
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incache, contents = self.cache.get(fname)
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assert(incache == True)
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v = self.files.getvalue()
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self.cache.update(fname, v)
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if self.solve:
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tprint('write:%d %d -> %d' % (fd, contents['data'], v))
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else:
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tprint('write:%d value? -> %d' % (fd, v))
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elif action == MICRO_CLOSE:
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fd = self.acts[self.acnt][1]
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fname = self.fd.lookup(fd)
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incache, contents = self.cache.get(fname)
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assert(incache == True)
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tprint('close:%d' % (fd))
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if self.cache.isdirty(fname):
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self.putfile(fname, contents['data'])
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self.cache.decref(fname)
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self.cache.checkvalid(fname)
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# useful to see
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self.cache.printstate(self.name)
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if self.solve and self.detail > 0:
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print ''
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# return that there is more left to do
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self.acnt += 1
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return 1
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#
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# main program
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#
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parser = OptionParser()
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parser.add_option('-s', '--seed', default=0, help='the random seed', action='store', type='int', dest='seed')
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parser.add_option('-C', '--clients', default=2, help='number of clients', action='store', type='int', dest='numclients')
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parser.add_option('-n', '--numsteps', default=2, help='ops each client will do', action='store', type='int', dest='numsteps')
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parser.add_option('-f', '--numfiles', default=1, help='number of files in server', action='store', type='int', dest='numfiles')
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parser.add_option('-r', '--readratio', default=0.5, help='ratio of reads/writes', action='store', type='float', dest='readratio')
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parser.add_option('-A', '--actions', default='', help='client actions exactly specified, e.g., oa1:r1:c1,oa1:w1:c1 specifies two clients; each opens the file a, client 0 reads it whereas client 1 writes it, and then each closes it',
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action='store', type='string', dest='actions')
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parser.add_option('-S', '--schedule', default='', help='exact schedule to run; 01 alternates round robin between clients 0 and 1. Left unspecified leads to random scheduling',
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action='store', type='string', dest='schedule')
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parser.add_option('-p', '--printstats', default=False, help='print extra stats', action='store_true', dest='printstats')
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parser.add_option('-c', '--compute', default=False, help='compute answers for me', action='store_true', dest='solve')
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parser.add_option('-d', '--detail', default=0, help='detail level when giving answers (1:server actions,2:invalidations,4:client cache,8:extra labels); OR together for multiple', action='store', type='int', dest='detail')
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(options, args) = parser.parse_args()
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|
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print 'ARG seed', options.seed
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print 'ARG numclients', options.numclients
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print 'ARG numsteps', options.numsteps
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|
print 'ARG numfiles', options.numfiles
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|
print 'ARG readratio', options.readratio
|
|
print 'ARG actions', options.actions
|
|
print 'ARG schedule', options.schedule
|
|
print 'ARG detail', options.detail
|
|
print ''
|
|
|
|
seed = int(options.seed)
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|
numclients = int(options.numclients)
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|
numsteps = int(options.numsteps)
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|
numfiles = int(options.numfiles)
|
|
readratio = float(options.readratio)
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|
actions = options.actions
|
|
schedule = options.schedule
|
|
printstats = options.printstats
|
|
solve = options.solve
|
|
detail = options.detail
|
|
|
|
# with specific schedule, files are all specified by a single letter in specific actions list
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|
# but we ignore this for now...
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|
|
|
zassert(numfiles > 0 and numfiles <= 26, 'main: can only simulate 26 or fewer files, sorry')
|
|
zassert(readratio >= 0.0 and readratio <= 1.0, 'main: read ratio must be between 0 and 1 inclusive')
|
|
|
|
# start it
|
|
random.seed(seed)
|
|
|
|
# files in server to begin with
|
|
f = files(numfiles)
|
|
|
|
# make server
|
|
s = server(f, solve, detail)
|
|
|
|
clients = []
|
|
|
|
if actions != '':
|
|
# if specific actions are specified, figure some stuff out now
|
|
# e.g., oa1:ra1:ca1,oa1:ra1:ca1 which is list of 0's actions, then 1's, then...
|
|
cactions = actions.split(',')
|
|
if numclients != len(cactions):
|
|
numclients = len(cactions)
|
|
i = 0
|
|
for clist in cactions:
|
|
clients.append(client('c%d' % i, i, s, f, [], len(clist), clist, solve, detail))
|
|
i += 1
|
|
else:
|
|
# else, make random clients
|
|
for i in range(numclients):
|
|
clients.append(client('c%d' % i, i, s, f, [readratio, 1.0], numsteps, '', solve, detail))
|
|
|
|
# tell server about these clients
|
|
s.setclients(clients)
|
|
|
|
# init print out for clients
|
|
print '%12s' % 'Server', '%12s' % ' ',
|
|
for c in clients:
|
|
print '%13s' % c.getname(), '%13s' % ' ',
|
|
print ''
|
|
|
|
# main loop
|
|
#
|
|
# over time, pick a random client
|
|
# have it do one thing, show what happens
|
|
# move on to next and so forth
|
|
|
|
s.filestats(True)
|
|
|
|
# for use with specific schedule
|
|
schedcurr = 0
|
|
|
|
# check for legal schedule (must include all clients)
|
|
if schedule != '':
|
|
for i in range(len(clients)):
|
|
cnt = 0
|
|
for j in range(len(schedule)):
|
|
curr = schedule[j]
|
|
if int(curr) == i:
|
|
cnt += 1
|
|
zassert(cnt != 0, 'main: client %d not in schedule:%s, which would never terminate' % (i, schedule))
|
|
|
|
# RUN the schedule (either random or specified by user)
|
|
numrunning = len(clients)
|
|
while numrunning > 0:
|
|
if schedule == '':
|
|
c = pickrand(clients)
|
|
else:
|
|
idx = int(schedule[schedcurr])
|
|
# print 'SCHEDULE DEBUG:: schedule:', schedule, 'schedcurr', schedcurr, 'index', idx
|
|
c = clients[idx]
|
|
schedcurr += 1
|
|
if schedcurr == len(schedule):
|
|
schedcurr = 0
|
|
rc = c.step(clients.index(c))
|
|
if rc == 0:
|
|
numrunning -= 1
|
|
|
|
|
|
s.filestats(solve)
|
|
|
|
if printstats:
|
|
s.stats()
|
|
for c in clients:
|
|
c.stats()
|
|
|