high kswapd CPU usage when executing binaries from NFS w/ CMA and COMPACTION

[Florian Fainelli]

Hi all,

I am experiencing high kswapd CPU usage on an ARMv7 system running
3.8.13 when executing relatively large binaries from NFS. When this
happens kswapd consumes around 55-60% CPU usage and the applications
takes a huge time to load.

My system has both CONFIG_CMA and CONFIG_COMPACTION enabled and
turning off CONFIG_COMPACTION does seem to make things slightly better
since kswapd does not take much CPU usage if at all and the
application loads with its expected loading time.

Attached are the contents of /proc/zoneinfo, vmstat and meminfo when
the system works correctly and their counterparts when the system is
busy in kswapd.

Any pointers to patches I should eventually backport or try would be
much appreciated!

Thanks!
-- 
Florian

Attachment: meminfo-working
Description: Binary data

Attachment: vmstat-working
Description: Binary data

Attachment: zoneinfo-working
Description: Binary data

Attachment: meminfo-bogus
Description: Binary data

Attachment: vmstat-bogus
Description: Binary data

Attachment: zoneinfo-bogus
Description: Binary data