similar to: [PATCH v2] Btrfs: improve multi-thread buffer read

While testing with my buffer read fio jobs[1], I find that btrfs does not perform well enough. Here is a scenario in fio jobs: We have 4 threads, "t1 t2 t3 t4", starting to buffer read a same file, and all of them will race on add_to_page_cache_lru(), and if one thread successfully puts its page into the page cache, it takes the responsibility to read the page''s data. And

Suppose I have "Orange1" data like this. TIME1 RESPONSE RESPSTAT RESPUT REFID ARM SUBARM 0 299.5 Mean 8-item scale 68 0 0 0 287 Median 8-item scale 68 0 0 0 303.9 Mean 8-item scale 68 1 0 0 286 Median 8-item scale 68 1 0 0 295 Mean 8-item scale 85 0 0 12 254 Mean 8-item scale 85 0 0 0 287 Mean 8-item scale 85 1 0 12 216 Mean

From: Wade Cline <clinew@linux.vnet.ibm.com> This patch is only an RFC. My internship is ending and I was hoping to get some feedback and incorporate any suggestions people may have before my internship ends along with life as we know it (this Friday). The filesystem should mount/umount properly but tends towards the explosive side when writes start happening. My current focus is on

This series implements NAPI + kthread 1:1 model for Xen netback. This model - provides better scheduling fairness among vifs - is prerequisite for implementing multiqueue for Xen network driver The first two patches are ground work for the third patch. They aim to reduce memory footprint of netback. The third patch has the real meat: - make use of NAPI to mitigate interrupt - kthreads are

Hi, The following series of patches implements in btrfs an ioctl to do out-of-band deduplication of file extents. To be clear, this means that the file system is mounted and running, but the dedupe is not done during file writes, but after the fact when some userspace software initiates a dedupe. The primary patch is loosely based off of one sent by Josef Bacik back in January, 2011.

Use access_extent_buffer_page() to point at btree location of inline compressed data so it can be inflated without a memcopy. Signed-off-by: jim owens <jowens@hp.com> Signed-off-by: jim owens <jim6336@gmail.com> --- V2 fixes whitespace checkpatch warning fs/btrfs/extent_io.c | 16 ++++++++++++++++ fs/btrfs/extent_io.h | 3 +++ 2 files changed, 19 insertions(+), 0 deletions(-)

In clear_extent_bit, it is enough that next node is adjacent in tree level. Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com> --- fs/btrfs/extent_io.c | 3 +-- 1 files changed, 1 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index fcf77e1..e941cc4 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -577,8 +577,7 @@ hit_next: if

A user has encountered a NULL pointer kernel oops in btrfs when encountering media errors. The problem has been identified as an unhandled NULL pointer returned from find_get_page(). This modification simply checks for a NULL page, and returns with an error if found (the extent_range_uptodate() function returns 1 on errors). After testing this patch, the user reported that the error with the

Hi, seem to keep running into a wall here. I can''t find any resources on site navigation that can deal with any model being in the nav, allow nesting, and can dynamically update. So I thought about it for a while, and decided on a MenuItems class, which contained the position of the child in relation to it''s siblings, where the parent and the child were polymorphic. Then a given

This series introduces a generic readahead interface for btrfs trees. The intention is to use it to speed up scrub in a first run, but balance is another hot candidate. In general, every tree walk could be accompanied by a readahead. Deletion of large files comes to mind, where the fetching of the csums takes most of the time. Also the initial build-ups of free-space-caches and

While testing raid-auto-repair patches I''m going to send out later, I just found the very last bug in my current scrub patch series: Changelog v4->v5: - fixed a deadlock when fixup is taking longer while scrub is about to end Original message follows: ------------------------ This patch set introduces two new features for scrub. They share the backref iteration code which is the

Hi all - Here''s my current error handling patchset, against 3.1-rc8. Almost all of this patchset is preparing for actual error handling. Before we start in on that work, I''m trying to reduce the surface we need to worry about. It turns out that there is a ton of code that returns an error code but never actually reports an error. The patchset has grown to 65 patches. 46 of them

hi, I am reading Modern Applied Statistics with S 4th ed$B!#(B page4 have these two lines: > library(MASS) > data(chem) # needed in R only but I find withou the line " data(chem)" I can still access chem, isn't it? is it unnecessary or something i missed here? thanks for the replay in advance.

bio_add_page() requires non-NULL bio ptr for dereferencing. Signed-off-by: Peter Teoh <htmldeveloper@gmail.com> --- extent_io.c.orig1 2008-03-16 12:43:59.000000000 +0800 +++ extent_io.c 2008-03-16 12:45:03.000000000 +0800 @@ -1729,6 +1729,7 @@ static int submit_extent_page(int rw, st if (bio_ret && *bio_ret) { bio = *bio_ret; + BUG_ON(!bio);

Hi gang, Here''s some trivial cleanups that I''ve built up while reading through the code. They''ve been run through xfstests -g quick. - z -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html

So both Liu and I made huge messes of find_lock_delalloc_range trying to fix stuff, me first by fixing extent size, then him by fixing something I broke and then me again telling him to fix it a different way. So this is obviously a candidate for some testing. This patch adds a pseudo fs so we can allocate fake inodes for tests that need an inode or pages. Then it addes a bunch of tests to make

Liu fixed part of this problem and unfortunately I steered him in slightly the wrong direction and so didn''t completely fix the problem. The problem is we limit the size of the delalloc range we are looking for to max bytes and then we try to lock that range. If we fail to lock the pages in that range we will shrink the max bytes to a single page and re loop. However if our first page

This adds a leak decoder callback so that slab destruction can use to generate debugging output for the allocated objects. Callers like btrfs are using their own leak tracking which will manage allocated objects in a list(or something else), this does indeed the same thing as what slab does. So adding a callback for leak tracking can avoid this as well as runtime overhead. (The idea is from

This adds a leak decoder callback so that kmem_cache_destroy() can use to generate debugging output for the allocated objects. Callers like btrfs are using their own leak tracking which will manage allocated objects in a list(or something else), this does indeed the same thing as what slab does. So adding a callback for leak tracking can avoid this as well as runtime overhead. Signed-off-by:

Hi all - The following 9 patches add more error handling to the btrfs code: - Add btrfs_panic - Catch locking failures in {set,clear}_extent_bit - Push up set_extent_bit errors to callers - Push up lock_extent errors to callers - Push up clear_extent_bit errors to callers - Push up unlock_extent errors to callers - Make pin_down_extent return void - Push up btrfs_pin_extent errors to