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| author | Andreas Gerstmayr <andreas.gerstmayr@catalysts.cc> | 2017-01-10 14:17:56 +0100 |
|---|---|---|
| committer | Ilya Dryomov <idryomov@gmail.com> | 2017-02-20 12:16:05 +0100 |
| commit | 7c94ba27903c3c46c5829e96efb7c2a8ab7510e9 (patch) | |
| tree | ffbc7ec7dfc898703ef368c71288a20b9e14a7aa | |
| parent | 0fbc5360bf433ffeccbb94ef806d637049899741 (diff) | |
| download | lwn-7c94ba27903c3c46c5829e96efb7c2a8ab7510e9.tar.gz lwn-7c94ba27903c3c46c5829e96efb7c2a8ab7510e9.zip | |
ceph: set io_pages bdi hint
This patch sets the io_pages bdi hint based on the rsize mount option.
Without this patch large buffered reads (request size > max readahead)
are processed sequentially in chunks of the readahead size (i.e. read
requests are sent out up to the readahead size, then the
do_generic_file_read() function waits until the first page is received).
With this patch read requests are sent out at once up to the size
specified in the rsize mount option (default: 64 MB).
Signed-off-by: Andreas Gerstmayr <andreas.gerstmayr@catalysts.cc>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Yan, Zheng <zyan@redhat.com>
| -rw-r--r-- | Documentation/filesystems/ceph.txt | 5 | ||||
| -rw-r--r-- | fs/ceph/super.c | 8 | ||||
| -rw-r--r-- | fs/ceph/super.h | 4 |
3 files changed, 12 insertions, 5 deletions
diff --git a/Documentation/filesystems/ceph.txt b/Documentation/filesystems/ceph.txt index f5306ee40ea9..0b302a11718a 100644 --- a/Documentation/filesystems/ceph.txt +++ b/Documentation/filesystems/ceph.txt @@ -98,11 +98,10 @@ Mount Options size. rsize=X - Specify the maximum read size in bytes. By default there is no - maximum. + Specify the maximum read size in bytes. Default: 64 MB. rasize=X - Specify the maximum readahead. + Specify the maximum readahead. Default: 8 MB. mount_timeout=X Specify the timeout value for mount (in seconds), in the case diff --git a/fs/ceph/super.c b/fs/ceph/super.c index 6bd20d707bfd..a0a0b6d02f89 100644 --- a/fs/ceph/super.c +++ b/fs/ceph/super.c @@ -952,6 +952,14 @@ static int ceph_register_bdi(struct super_block *sb, fsc->backing_dev_info.ra_pages = VM_MAX_READAHEAD * 1024 / PAGE_SIZE; + if (fsc->mount_options->rsize > fsc->mount_options->rasize && + fsc->mount_options->rsize >= PAGE_SIZE) + fsc->backing_dev_info.io_pages = + (fsc->mount_options->rsize + PAGE_SIZE - 1) + >> PAGE_SHIFT; + else if (fsc->mount_options->rsize == 0) + fsc->backing_dev_info.io_pages = ULONG_MAX; + err = bdi_register(&fsc->backing_dev_info, NULL, "ceph-%ld", atomic_long_inc_return(&bdi_seq)); if (!err) diff --git a/fs/ceph/super.h b/fs/ceph/super.h index a80a915ca247..f3f9215abf8e 100644 --- a/fs/ceph/super.h +++ b/fs/ceph/super.h @@ -45,8 +45,8 @@ #define ceph_test_mount_opt(fsc, opt) \ (!!((fsc)->mount_options->flags & CEPH_MOUNT_OPT_##opt)) -#define CEPH_RSIZE_DEFAULT 0 /* max read size */ -#define CEPH_RASIZE_DEFAULT (8192*1024) /* readahead */ +#define CEPH_RSIZE_DEFAULT (64*1024*1024) /* max read size */ +#define CEPH_RASIZE_DEFAULT (8192*1024) /* max readahead */ #define CEPH_MAX_READDIR_DEFAULT 1024 #define CEPH_MAX_READDIR_BYTES_DEFAULT (512*1024) #define CEPH_SNAPDIRNAME_DEFAULT ".snap" |