Re: [PATCH] VM tuning patch, take 2

[Jonathan Morton <chromi@cyberspace.org>]

>-       free += (dentry_stat.nr_unused * sizeof(struct dentry)) >>PAGE_SHIFT;
>-       free += (inodes_stat.nr_unused * sizeof(struct inode)) >> PAGE_SHIFT;
>+       /* free += (dentry_stat.nr_unused * sizeof(struct dentry)) >>
>PAGE_SHIFT;
>+          free += (inodes_stat.nr_unused * sizeof(struct inode)) >>
>PAGE_SHIFT;
>+        */
>
>
>On workloads full of dentries/inodes, allocations are going to fail with
>this change (remember most dentries/inodes _are_ usually freeable).

OK.  I made that change to help bring vm_enough_memory() and
out_of_memory() in line with each other, so if we put that back in, it
needs to be put in out_of_memory() as well.

As it happens, the dentry and inode caches get shrunk under VM pressure,
and so by the time swap is full and buffers+cache are a minimum size, these
caches will normally also be shrunk to their furthest sensible extent.

--------------------------------------------------------------
from:     Jonathan "Chromatix" Morton
mail:     chromi@cyberspace.org  (not for attachments)

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