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Subject2.1.103 cache size still too big
The only way to read with Pine linux-kernel at the end of the month
without wait for ages on my 32Mbye machine on 2.1.103 is setting:

root@dragon:/proc/sys/vm# cat pagecache
0 1 75

If I leave pagecache sysctl as default (15 ... 75 if I remember well)
performance drop since Pine got swapped out while is reading linux-kernel
folder.

Setting to 1 or to 0 the % of the memory that must be used for the cache
helps a lot, but sure something is still broken since the system at beast
leave 8Mbyte of memory in the cache while Pine opens _one_ linux-kernel
folder (this `free` is been run after a while so it appears of only
6Mbyte):

root@dragon:/proc/sys/vm# free
total used free shared buffers cached
Mem: 31100 30444 656 8436 980 6884
-/+ buffers/cache: 22580 8520
Swap: 52412 8752 43660

Note also that buffers are _always_ 980Kbyte.

If I leave pagecache as default and I open linux-kernel these days (two
day before start with an new empty folder) I get ~20Mbyte memory used by
the cache, ~20Mbyte swapped out and 8Mbyte of memory used to run software,
then ton of pagefault stall the system.

If I start _two_ Pine and open _two_ linux-kernel folder at the same time,
with pagecache set to 0 as first field (the only way to do it I think ;-),
the cache got reduced to 4 Mbyte (and 20Mbyte got swapped out) so sure it'
s not a problem of used unfreeable kernel structures since the more I open
things the more the cache got reduced.

Note also that 15 xx 75 got reasonable as default setting since 15% of
32Mbyte are 4Mbyte and I like this value when the system is low of memory.

Usually I don' t run application that uses large files except Pine...

I hope somebody will fix cache memory management before 2.2. I don' t
bother about cache speed, I bother about use the system.

Andrea[s] Arcangeli





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