I find out that python's VM seems to be very unfriendly with CPU-Cache.
see: http://stackoverflow.com/questions/32163585/how-to-handle-cpu-cache-in-python-or-fastest-way-to-call-a-function-once http://stackoverflow.com/questions/32153178/python-functionor-a-code-block-runs-much-slower-with-a-time-interval-in-a-loop for example: ******************************************* import time a = range(500) sum(a) for i in range(1000000): #just to create a time interval, seems this disturb cpu cache? pass st = time.time() sum(a) print (time.time() - st)*1e6 ********************************************* time:> 100us another case: ********************************************* import time a = range(500) for i in range(100000): st = time.time() sum(a) print (time.time() - st)*1e6 ********************************************* time:~ 20us we can see when running frequently, the code becomes much faster. is there a solution? I feel this question is very difficult. one must has indepth unstanding about the mechanism of python virtual machine, c and cpu-cache. Do you have any suggestion about where to post this question for a possible answer? -- https://mail.python.org/mailman/listinfo/python-list
