Date: Tue, 8 Oct 2002 12:59:24 -0700 (PDT) From: Don Lewis <dl-freebsd@catspoiler.org> To: olli@secnetix.de Cc: freebsd-hackers@FreeBSD.ORG Subject: Re: Mount option "nomtime"? Message-ID: <200210081959.g98JxOvU036374@gw.catspoiler.org> In-Reply-To: <200210081908.g98J809u055938@lurza.secnetix.de>
next in thread | previous in thread | raw e-mail | index | archive | help
On 8 Oct, Oliver Fromme wrote: > I should have been more specific in my examples. Sorry. > > Think about INN with using cycbuffers (CNFS) when storing > news articles (which is pretty standard on fullfeed news > servers). Those cycbuffers are a bunch of large files. > Their size never changes, but a lot of data is written to > them all the time. The same goes for the overview data > when using the so-called buffindexed storage. INN itself > does not need the mtime information of the buffer files. > > Another example would be "oops", which is a very fast, > lightweight web proxy. It uses cyclic buffer files to > store the cached data, similar to INN's CNFS. > > I think in the above cases, a "nomtime" option would indeed > save some unnecessary overhead. Probably not much, especially if you are using soft updates. The in-kernel copy of the inode will get updated on every write, but the on-disk copy will only get written when the soft updates timer for it goes off, which I think would be once every 10 seconds and is tunable. I don't think you'll see much reduction in load compared to all the other I/O that's going on. Noatime won't help much in your examples either. It only buys you a lot if the data is spread over a large number of files. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200210081959.g98JxOvU036374>