Comment 528 for bug 620074

Tried with recent official master: 18cb657ca1bafe635f368346a1676fb04c512edf

http://vi-server.org/vi/12309_report/linux-2.6.36-09212-g18cb657_i686-sysinfo.tar.bz2

While running "pv /dev/zero > qqq" (http://vi-server.org/vi/12309_report/fill.txt), after about 2 GB I get pagefaults: http://vi-server.org/vi/12309_report/pagefault.txt http://vi-server.org/vi/12309_report/pagefault2.txt

If I try deadline or noop scheduler, I still get pagefaults, but after about 5 GB of copied data (and probably not that often)

In case of cfq the speed is jumping between 10 MB/s to 200 MB/s.

In case of deadline or noop it is more stable, around 40 MB/s

Trying
> echo 10 > /proc/sys/vm/vfs_cache_pressure
> echo 4096 > /sys/block/sda/queue/nr_requests
> echo 4096 > /sys/block/sda/queue/read_ahead_kb
> echo 100 > /proc/sys/vm/swappiness
> echo 0 > /proc/sys/vm/dirty_ratio
> echo 0 > /proc/sys/vm/dirty_background_ratio
on this kernel leads to low filling speed (lover than 10 MB/s, measured with pv)
Also after applying that settings applications (starting with gpg2) begin to hang in uninterruptible sleep with these settings. I cannot stop filling (probably it hangs too).

P.S. Using this kernel I also cannot start X server.

If somebody want, I can try other settings, other kernel revisions, patches, other config.