On Sat, 6 Oct 2007, Rob Mueller wrote: > As it turns out, the memory leaks weren't critical, because the the pages do > seem to be reclaimed when needed, though it was annoying not knowing exactly > how much memory was really free/used. The biggest problem was that with > cyrus you have millions of small files, and with a 32bit linux kernel the > inode cache has to be in low memory, severely limiting how many files the OS > will cache. > > See this blog post for the gory details, and why a 64-bit kernel was a nice > win for us. > > http://blog.fastmail.fm/2007/09/21/reiserfs-bugs-32-bit-vs-64-bit-kernels-cache-vs-inode-memory/ Yesterday I checked my own Cyrus servers to see if I was running out of lowmem, and it sure looked like it. Lowmem had only a couple MB free, and I had 2GB of free memory that was not being used for cache. I checked again today and everything seems to be fine - 150MB of lowmem free and almost no free memory (3GB cached)! Grrr. Anyways, I was looking into building a 64-bit kernel. I'm running Debian Sarge (I know, old) on a Dell 2850 with Intel Xeon (Nocona) CPUs and 4GB RAM. My kernel version is 2.6.14.5, built from kernel.org sources. It has "High Memory Support (64GB)" selected. When I run menuconfig, I'm not seeing any obvious place to switch from 32-bit to 64-bit. Could you elaborate a bit about how you switched to a 64-bit kernel? Also, are you running a full 64-bit distro, or just a 64-bit kernel? Thanks, Andy ---- Cyrus Home Page: http://cyrusimap.web.cmu.edu/ Cyrus Wiki/FAQ: http://cyrusimap.web.cmu.edu/twiki List Archives/Info: http://asg.web.cmu.edu/cyrus/mailing-list.html
