Bauer, You said you get 60k to 80k hits/hour some times, and this is eating your memory away. If you have Apache or IHS installed, you should consider taking a look on httpd.conf to reduce the webserver memory footprint. By default, the httpd.conf loads a whole bunch of modules, for directory authentication, log formats, indexing and so. And the unused modules have a double burden: they increase the memory usage AND slows down your server (more memory means more paging for zVM, more cicle-stealing from CP and more unhappy clients). Disable everything you don't need and you will see your webserver flying and your httpd memory usage at bay. If you have the Keep-alive directive active (you should, it's good for you), consider reducing the default timeout value. I think 2 seconds a good value, so your server doesn't keep waiting 15 seconds until releasing the connection. This means more throughput with less memory.
Mauro http://mauro.limeiratem.com - registered Linux User: 294521 Scripture is both history, and a love letter from God. On Wed, Nov 2, 2011 at 10:42 PM, Shane <[email protected]> wrote: > On Wed, 2 Nov 2011 11:29:40 -0400 Richard Troth wrote: > >> So what you're seeing >> is random pages which got pushed out at various times during the >> stress period. If not needed, they will sit there forever. > > Well, maybe not "forever" ... ;-) > This lazy (de-)allocation behaviour of Linux is worth remembering. It's > just too expensive to continually run the q's to clean this up. Later > kernels expose the per-pid (actual) swap usage - I haven't figured out > if there is yet a reliable means of discerning disk vs. cache swap > usage. > >> I like to >> differentiate between "swap occupancy" and "swap movement". The >> occupancy doesn't really hurt you in terms of response time. > > Most of the time. > If memory pressure ramps up *really* quickly, kswapd gets kicked into > action to run the q's to free up pages. And it can cycle back through > chasing enough memory to free. > Not likely in this scenario, but if kswapd needs to work, you wait. > > Shane ... > > ---------------------------------------------------------------------- > For LINUX-390 subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO LINUX-390 or visit > http://www.marist.edu/htbin/wlvindex?LINUX-390 > ---------------------------------------------------------------------- > For more information on Linux on System z, visit > http://wiki.linuxvm.org/ > ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
