Altering queries?
Dustin Sallings
dustin at spy.net
Thu Sep 20 19:36:59 UTC 2007
On Sep 20, 2007, at 12:10 , K J wrote:
> How about storing the list of the user's friends in cache also?
> The only problem here though, is what if the user has tens of
> thousands of friends, for instance?
Bah, just declare that user to be a liar and kick them out of your
system. :)
I just did some hand-wavy math on that:
>>> import random
>>> r=random.Random()
>>> import sets
>>> s=sets.Set([r.randint(1, 10000000) for x in range(30000)])
>>> len(s)
29950
>>> len(','.join([str(i) for i in s]))
236301
>>> import zlib
>>> compressed=zlib.compress(','.join([str(i) for i in s]), 9)
>>> len(compressed)
109568
So, a user with about 30k friends with numeric IDs fairly even
distributed from 1 to 10,000,000 (my average ID was 4,979,961, min
was 236, max was 9,999,931) would take a little over 100k of cache
when comma separated and compressed.
I would expect the normal case to be much smaller.
--
Dustin Sallings
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