Re: how to get a silent harddisk?
Hi!
On Fri, 12 Sep 2003 14:47:04 -0600 (MDT) "Jacob Anawalt" <jacob@cachevalley.com> wrote:
> Tom Allison said:
> > Jacob Anawalt wrote:
> >> Joachim Förster said:
> >>
> >>>Does anybody know, why squid uses the harddisk although its (empty disk
> >>>cache, logs and other status files are on the tmpfs)?
> >>>
> >> I don't know why it uses the hard disk, but if it is only reading those
> >> files and there is enough memory that they are cached in the kernel file
> >> cache, then perhaps the atime is being updated and that is causing the
> >> disk to spin up?
> >>
> >> Are you mounting with the noatime option?
> >>
> >> Maybe there's another http proxy that doesn't require any disk access?
> >>
> >> I am interested in following this thread. I would like to set up a
> >> similar
> >> computer, with as few fans and spinning drives (zero would be ideal) as
> >> possible while staying inexpensive and low-power.
> >>
> For me, squid disk access while someone on my internal network is using
> the proxy is not an issue. If squid were spinning up the drive when
> 'nothing'* is happening, calling sync()/fsync() for some odd reason then
> that would be annoying. I'm running a gateway w/ squid right now, but I
> haven't tried to stop the disk from spinning when squid is running.
Well, in the end I in fact want to have a PC without spinning up the disk at all, even when somebody is using it. When somebody is using sshd it whould be OK, but the use of dhcpd, squid*, isdnutils, dnsmasq should not bring up the disk.
*squid only with RAM cache, no disk cache!
> I am unclear from Joachim's email if Squid is spinning up the disk all the
> time for him, every x seconds, or only when the proxy is being used. If
> it's only the latter then for my needs that's OK.
Sorry, for me squid is spinning up the disk all the time, even when not in use.
> It still seems odd if writes are spinning up the drive with the read only
> setting. Maybe some file squid wants to read keeps being dropped from file
> cache between accesses because other programs or more frequently accessed
> files are using all the memory? (Ie, because squid is set to use XMb in
> memory, is there still enough free memory to cache all the files squid
> wants to read. Add to that all other running program's requirements.)
I don't know. I moved the whole /var and /tmp things of squid to a tmpfs, so the files are in memory?
> the site. Joachim, you could try LRP, but load everything into memory from
> your hd instead of from a floppy.
Hmmm, have to try it out ...
> noflushd seems to be a good step in that direction. I'll try it out.
> Thanks for mentioning it in the first post. I've read more about it and
> see that it's suppose to buffer those atime writes, so sorry about that
> bad guess.
noflushd works - but I had to change the values in /proc/sys/vm/bdflush, too, to keep the disk silent for a longer time than just a few minutes.
I haven't tried it yet, but I think the noatime option may be good anyway - in "addition" to noflushd ...
Thanks,
Joachim
Reply to: