On 2013-01-30, Constantine A. Murenin <muren...@gmail.com> wrote: > Hello misc@, > > On OpenBSD 5.2 amd64, I'm storing 1.4GB of source code files and about > 8x 150MB indices on an mfs partition, plus a gig or two of other > automatically-generated files. > > If I run mount_mfs to load all this stuff from a regular drive, then > the amount of memory used by mount_mfs(8) is about the same as the > amount of Used disc space as reported by df(1). > > However, if I re-run index generation on an mfs, then after it's all > done, memory usage by mount_mfs(8) noticeably exceeds Used disc space. > As a workaround, I found that it's possible to copy all the files > over to a new mount_mfs(8) process, after the indices have been > re-generated, and the new process will at first have a much better > memory usage, but this seems a little inconvenient and would also > require a temporary burst of extra RAM to accomplish. > > Should I worry that on a 6GB partition that is only 4GB full, > mount_mfs uses 5GB of memory after about 3GB of data gets mingled? Is > mount_mfs swappable? If I end up being short on memory, would that > extra 1GB from mount_mfs(8) be swapped out without affecting the > performance? Or is there a way to run some kind of garbage collector > or otherwise improve on an mfs memory use? > > % df -hi | fgrep -e Used -e mfs ; mount | fgrep mfs ; ps aux | fgrep > -e USER -e mfs > Filesystem Size Used Avail Capacity iused ifree %iused Mounted on > mfs:18610 5.9G 4.1G 1.5G 73% 439864 357702 55% /grok/mfs > mfs:18610 on /grok/mfs type mfs (asynchronous, local, nodev, nosuid, > size=12582912 512-blocks) > USER PID %CPU %MEM VSZ RSS TT STAT STARTED TIME COMMAND > root 18610 0.0 40.2 6291936 5048352 ?? Is Sun07PM 0:22.56 > /sbin/mount_mfs -o rw -s6G -f2048 > > > Cheers, > Constantine. > >
This is expected with mfs, don't set the filesystem to be larger than the amount of memory you would like it to use. I don't know how it behaves with swapping.
