search for: segmap

Author: praks Repository: /hg/zfs-crypto/gate Revision: 4c3b7ab574cc73502effa96c11c293e04fd54309 Log message: 6256083 Need a lightweight file page mapping mechanism to substitute segmap 6387639 segkpm segment set to incorrect size for amd64 Files: create: usr/src/uts/common/vm/vpm.c create: usr/src/uts/common/vm/vpm.h update: usr/src/pkgdefs/SUNWhea/prototype_com update: usr/src/uts/common/Makefile.files update: usr/src/uts/common/fs/nfs/nfs3_vnops.c update: usr/src/uts/com...

Whats the default size of the file system cache for Solaris 10 x86 and can it be tuned? I read various posts on the subject and its confusing.. -- This message posted from opensolaris.org

...all block random I/O on ZFS, or any other documents that might explain what we''re seeing and give us guidance on how to most effectively deploy ZFS in an environment with heavy small block random I/O. The first anomaly, Brendan Gregg''s CacheKit Perl script fcachestat shows the segmap cache is hardly used (occasionally during the IOzone random read benchmark, while the disks are grabbing 20MB/s in aggregate, the segmap cache gets 100% hits for 1-3 attempts *every 10 seconds*--while all other samples are zero% for zero attempts. I don''t know the kernel I/O path as well...

One thing I''ve been confused about for a long time is the relationship between ZFS, the ARC, and the page cache. We have an application that''s a quasi-database. It reads files by mmap()ing them. (writes are done via write()). We''re talking 100TB of data in files that are 100k->50G in size (the files have headers to tell the app what segment to map, so mapped chunks

I am [trying to] perform a test prior to moving my data to solaris and zfs. Things are going very poorly. Please suggest what I might do to understand what is going on, report a meaningful bug report, fix it, whatever! Both to learn what the compression could be, and to induce a heavy load to expose issues, I am running with compress=gzip-9. I have two machines, both identical 800MHz P3 with