Re: ~500 megs cached yet 2.6.5 goes into swap hell

Paul Jackson
2004-04-30T01:02:15Z

Andrew wrote:
> fadvise(POSIX_FADV_DONTNEED) is ideal for this.

Perhaps ... perhaps not.

Just as the knobs "only reclaim pagecache" and "reclaim vfs caches
harder" had too big a scope (system-wide), using fadvise might have too
small a scope (currently cached pages of current task only).

If his background daemon is some shell script, say, that uses 'cat' to
generate the i/o to the other spindle, then he probably wants to be
marking that daemon job "don't let this entire job eat my pagecache",
not rebuilding a hacked up cat command with added POSIX_FADV_DONTNEED
calls every megabyte.

CKRM to the rescue ... ??

--
I won't rest till it's the best ...
Programmer, Linux Scalability
Paul Jackson <pj@sgi.com> 1.650.933.1373