Problem with stackless python, cannot write to a dict
- by ANON
I have simple map-reduce type algorithm, which I want to implement in python and make use of multiple cores.
I read somewhere that threads using native thread module in 2.6 dont make use of multiple cores. is that true?
I even implemented it using stackless python however i am getting into weird errors
[Update: a quick search showed that the stack less does not allows multiple cores
So are their any other alternatives?]
def Propagate(start,end):
print "running Thread with range: ",start,end
def maxVote(nLabels):
count = {}
maxList = []
maxCount = 0
for nLabel in nLabels:
if nLabel in count:
count[nLabel] += 1
else:
count[nLabel] = 1
#Check if the count is max
if count[nLabel] > maxCount:
maxCount = count[nLabel];
maxList = [nLabel,]
elif count[nLabel]==maxCount:
maxList.append(nLabel)
return random.choice(maxList)
for num in range(start,end):
node=MapList[num]
nLabels = [Label[k] for k in Adj[node]]
if (nLabels!=[]):
Label[node] = maxVote(nLabels)
else:
Label[node]=node
However in above code the values assigned to Label, that is the change in dictionary are lost.
Above propagate function is used as callable for MicroThreads (i.e. TaskLets)
