glusterfs.git/xlators/performance/read-ahead, branch release-7

libglusterfs: cleanup iovec functions

2019-06-11T13:28:07+00:00

This patch cleans some iovec code and creates two additional helper
functions to simplify management of iovec structures.

  iov_range_copy(struct iovec *dst, uint32_t dst_count, uint32_t dst_offset,
                 struct iovec *src, uint32_t src_count, uint32_t src_offset,
                 uint32_t size);

    This function copies up to 'size' bytes from 'src' at offset
    'src_offset' to 'dst' at 'dst_offset'. It returns the number of
    bytes copied.

  iov_skip(struct iovec *iovec, uint32_t count, uint32_t size);

    This function removes the initial 'size' bytes from 'iovec' and
    returns the updated number of iovec vectors remaining.

The signature of iov_subset() has also been modified to make it safer
and easier to use. The new signature is:

  iov_subset(struct iovec *src, int src_count, uint32_t start, uint32_t size,
             struct iovec **dst, int32_t dst_count);

    This function creates a new iovec array containing the subset of the
    'src' vector starting at 'start' with size 'size'. The resulting
    array is allocated if '*dst' is NULL, or copied to '*dst' if it fits
    (based on 'dst_count'). It returns the number of iovec vectors used.

A new set of functions to iterate through an iovec array have been
created. They can be used to simplify the implementation of other
iovec-based helper functions.

Change-Id: Ia5fe57e388e23392a8d6cdab17670e337cadd587
Updates: bz#1193929
Signed-off-by: Xavi Hernandez

New xlator option to control enable/disable of xlators in Gd2

2018-12-07T05:28:23+00:00

Since glusterd2 don't maintain the xlator option details in code, it
directly reads the xlators options table from `*.so` files. To support
enable and disable of xlator new option added to the option table with
the name same as xlator name itself.

This change will not affect the functionality with glusterd1.

Change-Id: I23d9e537f3f422de72ddb353484466d3519de0c1
updates: #302
Signed-off-by: Aravinda VK

all: add xlator_api to many translators

2018-12-06T07:54:28+00:00

Fixes: #164
Change-Id: I93ad6f0232a1dc534df099059f69951e1339086f
Signed-off-by: Amar Tumballi

libglusterfs: Move devel headers under glusterfs directory

2018-12-05T21:47:04+00:00

libglusterfs devel package headers are referenced in code using
include semantics for a program, this while it works can be better
especially when dealing with out of tree xlator builds or in
general out of tree devel package usage.

Towards this, the following changes are done,
- moved all devel headers under a glusterfs directory
- Included these headers using system header notation <> in all
code outside of libglusterfs
- Included these headers using own program notation "" within
libglusterfs

This change although big, is just moving around the headers and
making it correct when including these headers from other sources.

This helps us correctly include libglusterfs includes without
namespace conflicts.

Change-Id: Id2a98854e671a7ee5d73be44da5ba1a74252423b
Updates: bz#1193929
Signed-off-by: ShyamsundarR

libglusterfs: rename macros roof and floor to not conflict with math.h

2018-11-28T15:11:59+00:00

Change-Id: I666eeb63ebd000711b3f793b948d4e0c04b1a242
Signed-off-by: Raghavendra Gowdappa 
Updates: bz#1644629

all: fix the format string exceptions

2018-11-05T18:50:59+00:00

Currently, there are possibilities in few places, where a user-controlled
(like filename, program parameter etc) string can be passed as 'fmt' for
printf(), which can lead to segfault, if the user's string contains '%s',
'%d' in it.

While fixing it, makes sense to make the explicit check for such issues
across the codebase, by making the format call properly.

Fixes: CVE-2018-14661

Fixes: bz#1644763
Change-Id: Ib547293f2d9eb618594cbff0df3b9c800e88bde4
Signed-off-by: Amar Tumballi

Land part 2 of clang-format changes

2018-09-12T12:22:45+00:00

Change-Id: Ia84cc24c8924e6d22d02ac15f611c10e26db99b4
Signed-off-by: Nigel Babu

Land clang-format changes

2018-09-12T11:52:48+00:00

Change-Id: I6f5d8140a06f3c1b2d196849299f8d483028d33b

performance/read-ahead: stricter adherence to force-atime-update

2018-07-19T06:56:20+00:00

Throwaway read-ahead cache in fstat only if force-atime-update is
set. Note that fstat flushes read-ahead cache only for atime
consistency. However if atime consistency is needed user is required
to set force-atime-update which updates atime on backend fs even
though application reads are served from read-ahead cache. So, if user
has not set force-atime-update, atime won't be accurate and there is
no point in flushing read-ahead cache in fstats. mounts
requiring atime consistency have to mandatorily set
force-atime-update.

Also note that normally kernel interspers reads with fstat. So,
read-ahead is not effective as fstats flush read-ahead-cache. Instead
it regresses performance due to wasted network reads. It is
recommended to turn off read-ahead if applications require atime
consistency.

This patch is aimed at applications which don't require atime
consistency. Without atime consistency required, read-ahead cache is
effective and increases performance of sequential reads.

Change-Id: I122bbc410cee96661823f9c4b934383495c18446
Signed-off-by: Raghavendra G 
Fixes: bz#1601166

performance/read-ahead: throwaway read-ahead cache of all fds on writes on any fd

2018-05-29T02:28:19+00:00

This is to make sure applications that read and write on different fds
of the same file work.

This patch also fixes two other issues:
1. while iterating over the list of open fds on an inode, initialize
tmp_file to 0 for each iteration before fd_ctx_get to make sure we
don't carry over the history from previous iterations.
2. remove flushing of cache in flush and fsync as by themselves, they
don't modify the data

Change-Id: Ib9959eb73702a3ebbf90badccaa16b2608050eff
Signed-off-by: Raghavendra G 
Updates: bz#1512691