[PATCH] fadvise: avoid EINVAL if user input is valid

The kernel is not required to act on fadvise, so fail silently and ignore advice as long as it has a valid descriptor and parameters. Cc: linux-mm@kvack.org Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Eric Wong ...

Message posted on the February 24th, 2012 - 9:40 PM ET

[PATCH] fadvise: perform WILLNEED readahead in a workqueue

Applications streaming large files may want to reduce disk spinups and I/O latency by performing large amounts of readahead up front. Applications also tend to read files soon after opening them, so waiting on a slow fadvise may cause unpleasant ...

Message posted on the December 14th, 2012 - 8:00 PM ET

[PATCH] fadvise: introduce POSIX_FADV_DONTNEED_FS

Introduce a new fadvise flag to drop page cache pages of a single filesystem. At the moment it is possible to drop page cache pages via /proc/sys/vm/drop_pagecache or via posix_fadvise(POSIX_FADV_DONTNEED). The first method drops the whole page ...

Message posted on the April 27th, 2011 - 10:30 AM ET

[PATCH] fadvise: only initiate writeback for specified range with FADV_DONTNEED

Previously POSIX_FADV_DONTNEED would start writeback for the entire file when the bdi was not write congested. This negatively impacts performance if the file contians dirty pages outside of the requested range. This change uses ...

Message posted on the October 31st, 2011 - 11:20 AM ET

[PATCH] mm: fadvise: Drain all pagevecs if POSIX_FADV_DONTNEED fails to discard all pages

Rob van der Heij reported the following (paraphrased) on private mail. The scenario is that I want to avoid backups to fill up the page cache and purge stuff that is more likely to be used again (this is with s390x Linux on z/VM, so I don't give it ...

Message posted on the February 14th, 2013 - 7:10 AM ET

[PATCH 0/3] Volatile Ranges (v7) & Lots of words

After Kernel Summit and Plumbers, I wanted to consider all the various side-discussions and try to summarize my current thoughts here along with sending out my current implementation for review. Also: I'm going on four weeks of paternity leave in ...

Message posted on the September 28th, 2012 - 11:20 PM ET

[RFC] [PATCH v5 0/3] fadvise: support POSIX_FADV_NOREUSE

There were some reported problems in the past about trashing page cache when a backup software (i.e., rsync) touches a huge amount of pages (see for example [1]). This problem was mitigated by the Minchan's patch [2] and a proper use of fadvise() ...

Message posted on the February 11th, 2012 - 7:30 PM ET

[PATCH v2] fadvise: perform WILLNEED readahead asynchronously

Using fadvise with POSIX_FADV_WILLNEED can be very slow and cause user-visible latency. This hurts interactivity and encourages userspace to resort to background threads for readahead (or avoid POSIX_FADV_WILLNEED entirely). "strace -T" ...

Message posted on the December 24th, 2012 - 9:30 PM ET

fadvise interferes with readahead

Hi. First of all, I'm not subscribed to this list, so I'd suggest all replies copy me personally. I have been trying to implement some I/O pipelining in Postgres (ie: read the next data page asynchronously while working on the current page), and ...

Message posted on the November 9th, 2012 - 2:40 PM ET

[PATCH] [RFC] fadvise: Add _VOLATILE,_ISVOLATILE, and _NONVOLATILE flags

This patch provides new fadvise flags that can be used to mark file pages as volatile, which will allow it to be discarded if the kernel wants to reclaim memory. This is useful for userspace to allocate things like caches, and lets the kernel ...

Message posted on the November 21st, 2011 - 10:40 PM ET

[PATCH] mm, fadvise: don't return -EINVAL when filesystem has no optimization way

From: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Eric Wong reported his test suite was fail when /tmp is tmpfs. https://lkml.org/lkml/2012/2/24/479 Current,input check of POSIX_FADV_WILLNEED has two problems. 1) require ...

Message posted on the June 15th, 2012 - 4:40 PM ET

[PATCH v3] fadvise: introduce POSIX_FADV_DONTNEED_FS

Introduce a new fadvise flag to drop page cache pages of a single filesystem. At the moment it is possible to drop page cache pages via /proc/sys/vm/drop_pagecache or via posix_fadvise(POSIX_FADV_DONTNEED). The first method drops the whole page ...

Message posted on the April 29th, 2011 - 12:20 PM ET

fadvise DONTNEED implementation (or lack thereof)

I've recently been trying to track down the root cause of my server's persistent issue of thrashing horribly after being left inactive. It seems that the issue is likely my nightly backup schedule (using rsync) which traverses my entire 50GB home ...

Message posted on the November 4th, 2010 - 1:00 AM ET

[PATCH 0/2] [RFC] Volatile ranges (v4)

Ok. So here's another iteration of the fadvise volatile range code. I realize this is still a way off from being ready, but I wanted to post what I have to share with folks working on the various range/interval management ideas as well as update ...

Message posted on the March 16th, 2012 - 6:00 PM ET

patch fadvise