On 06/11/2010 07:56 AM, Balbir Singh wrote:
Just to be clear, let's say we have a mapped page (say of /sbin/init)
that's been unreferenced since _just_ after the system booted. We also
have an unmapped page cache page of a file often used at runtime, say
one from /etc/resolv.conf or /etc/passwd.
Which page will be preferred for eviction with this patch set?
In this case the order is as follows
1. First we pick free pages if any
2. If we don't have free pages, we go after unmapped page cache and
slab cache
3. If that fails as well, we go after regularly memory
In the scenario that you describe, we'll not be able to easily free up
the frequently referenced page from /etc/*. The code will move on to
step 3 and do its regular reclaim.
Still it seems to me you are subverting the normal order of reclaim. I
don't see why an unmapped page cache or slab cache item should be
evicted before a mapped page. Certainly the cost of rebuilding a dentry
compared to the gain from evicting it, is much higher than that of
reestablishing a mapped page.
--
error compiling committee.c: too many arguments to function
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