worse than it should be

Posted Sep 7, 2009 14:18 UTC (Mon) by mingo (guest, #31122)
In reply to: worse than it should be by job
Parent article: BFS vs. mainline scheduler benchmarks and measurements

What happens during big VM pressure rarely depends on the process scheduler. If you monitor your system during such situations you'll see there's plenty of idle CPU time - just nobody is able to make progress because everyone will be swapping around small fragments.

[ Or if there's a lot of CPU time used, it's all kswapd's ;-) ]

worse than it should be

Posted Sep 7, 2009 20:40 UTC (Mon) by alankila (guest, #47141) [Link]

compcache seems to really help about with making progress. Even if you are swapping, it's so fast that you can actually use your system: start new terminals, run top, etc. Even if the task is in an allocation frenzy and ends up OOM-killed, it does so with relatively little disk activity.

I really have a love affair with it compcache---to the point that I have given up all other types of swap and am now married to this single solution. It can also help with large images, especially those that are mostly single color. I imagine those pages compress very, very well...