Hi Peter, Also sprach Peter Smith <peter.smith@xxxxxxxxxxxxxxxxxx> (Thu, 12 Jan 2006 18:45:49 -0600): > Peter Smith wrote: > > Richard Mittendorfer wrote: > >> When downloading a cached file from the local squid, I just get > >about > 250 - 280kB/s. Even on localhost. Is this a limitation with > >diskd > serving files from cache or some intern limit? I also tried > >aufs, but > didn't get a better rate. I found a thread here about > >this, but it got > more into a diskd/aufs discussion :) and didn't > >provide a solution or > explains it. It doesn't look like it's > >disk/system related, > vmstat/top doesn't show > >> high load. > >> > >> linux 2.6 celeron 600MHz > >> squid-2.5.STABLE12 Debian GNU/Linux > >> 2 x cache_dir diskd 1G 8 128 on 2 x SCSI reiserfs > >> 32M cache_mem, acls, .. need more info? > > > > I too have experience this. I believe this is because Squid has > > built-in safeguards to keep users from flooding the disk and to even > > the load across all disks for all users. Another reason is Squid > > handles all requests in sequential order--client requests, server > > requests, and memory/disk cache reads/writes.. It is like a > > virtualized network handler or VM. It really doesn't want one client > > to kill all others.. That would explain it. It's even if I'm the only client and it's one big file that's retrieved, so it must be some kind of internal limit. I have to look into the source, maybe I can find it hardcoded somewhere. 256kB/s looks so artificial ;) In this particulae case I use squid to serve bigger cached objects (.deb's, kinda apt-cache) to a few clients. It's not horrible slow -- I'm fine with 260kB/s. I was just wondering what happens if you're on a faster line. Wouldn't squid slow things down too much then? > Btw, it still does have a lot to do with diskd/aufs... Read here > http://squid-docs.sourceforge.net/latest/html/x220.html#AEN318 Had a look at it. Doesn't look like debian's squid is compiled with async-io. Have to try if I got time for it. However, I'm quite sure it won't help here. Thx for the docs link - didn't know it. ..hmm - <coffee> - sure, debian's is async-io. Must be. aufs _is_ compiled in: --enable-storeio=ufs,aufs,diskd,null > Peter thx a lot, ritch
