Date: Sat, 8 Dec 2001 20:14:50 -0800 (PST) From: Doug Ambrisko <ambrisko@ambrisko.com> To: Matthew Dillon <dillon@apollo.backplane.com> Cc: freebsd-arch@FreeBSD.ORG Subject: Re: Using a larger block size on large filesystems Message-ID: <200112090414.fB94Eoa19371@ambrisko.com> In-Reply-To: <200112081909.fB8J9TB06131@apollo.backplane.com>
next in thread | previous in thread | raw e-mail | index | archive | help
Matthew Dillon writes: | :I know you've mentioned this before. Are there technical reasons behind | :this? I believe you mentioned something about the buffer cache? Would | :you be willing to add it as an option since so many others seem to want | :it? | | Most of the stuff that winds up in /tmp is garbage. There is no good | reason to burden our VM system with unnecessary garbage and I know of | no performance issues involved with people using /tmp files that requires | MFS or MD. It's an unnecessary waste of memory and an unnecessary burden | on our VM system. Unless you want a cvs pserver to run fast! I did some benchmarks a while back (port 4.2 I think) in which I had /tmp on soft-updates. It was a little faster on "cvs co freebsd" for example. CVS pserver was running on a dedicated machine and the CVS client was on another. Switched to MFS made a significant improvement. I don't have the number anymore (changed employers). I think the issue here is that CVS on the pserver checks out a sparse tree of the meta data for the each directory that you need. I recall directory operations are sync'd. So creating all the directories and syncing them becomes the gating factor. BTW we ended up sticking a lot of memory in that machine to prevent swaping. We had about 20 people using it. One thing I didn't try was mounting /tmp as async and maybe noatime. That might be an interesting thing to try. Doug A. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200112090414.fB94Eoa19371>