lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Thu, 28 Dec 2006 02:29:26 -0800 From: Andrew Morton <akpm@...l.org> To: Fengguang Wu <fengguang.wu@...il.com> Cc: "Zhang, Yanmin" <yanmin_zhang@...ux.intel.com>, LKML <linux-kernel@...r.kernel.org> Subject: Re: [PATCH] drop page cache of a single file On Thu, 28 Dec 2006 15:19:04 +0800 Fengguang Wu <fengguang.wu@...il.com> wrote: > On Wed, Dec 27, 2006 at 07:49:59PM -0800, Andrew Morton wrote: > > On Thu, 28 Dec 2006 11:17:25 +0800 > > "Zhang, Yanmin" <yanmin_zhang@...ux.intel.com> wrote: > > > > > Currently, by /proc/sys/vm/drop_caches, applications could drop pagecache, > > > slab(dentries and inodes), or both, but applications couldn't choose to > > > just drop the page cache of one file. An user of VOD (Video-On-Demand) > > > needs this capability to have more detailed control on page cache release. > > > > The posix_fadvise() system call should be used for this. Probably in > > combination with sys_sync_file_range(). > > Yanmin: I've been using the fadvise tool from > http://www.zip.com.au/~akpm/linux/patches/stuff/ext3-tools.tar.gz > > It's a nice tool: > > % fadvise > Usage: fadvise filename offset length advice [loops] > advice: normal sequential willneed noreuse dontneed asyncwrite writewait > % fadvise /var/sparse 0 0x7fffffff dontneed > I was a bit reluctant to point at that because it has nasty hacks to make it mostly-work on old glibc's which don't implement posix_fadvise(). Hopefully if you're running a recent distro, you have glibc support for fadvise() and it's possible to write a portable version of that app which doesn't need to know about per-arch syscall numbers. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists