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| author | Constantine Shulyupin <const@MakeLinux.com> | 2018-09-06 15:37:06 +0300 |
|---|---|---|
| committer | Miklos Szeredi <mszeredi@redhat.com> | 2018-10-01 10:07:06 +0200 |
| commit | 5da784cce4308ae10a79e3c8c41b13fb9568e4e0 (patch) | |
| tree | f55416dec7532814d30c1dbd415ef11baec9fc7a /fs/fuse/dev.c | |
| parent | 8a7aa286ab67d7dfac8abbefab899597b5977c9a (diff) | |
| download | linux-5da784cce4308ae10a79e3c8c41b13fb9568e4e0.tar.gz linux-5da784cce4308ae10a79e3c8c41b13fb9568e4e0.tar.bz2 linux-5da784cce4308ae10a79e3c8c41b13fb9568e4e0.zip | |
fuse: add max_pages to init_out
Replace FUSE_MAX_PAGES_PER_REQ with the configurable parameter max_pages to
improve performance.
Old RFC with detailed description of the problem and many fixes by Mitsuo
Hayasaka (mitsuo.hayasaka.hu@hitachi.com):
- https://lkml.org/lkml/2012/7/5/136
We've encountered performance degradation and fixed it on a big and complex
virtual environment.
Environment to reproduce degradation and improvement:
1. Add lag to user mode FUSE
Add nanosleep(&(struct timespec){ 0, 1000 }, NULL); to xmp_write_buf in
passthrough_fh.c
2. patch UM fuse with configurable max_pages parameter. The patch will be
provided latter.
3. run test script and perform test on tmpfs
fuse_test()
{
cd /tmp
mkdir -p fusemnt
passthrough_fh -o max_pages=$1 /tmp/fusemnt
grep fuse /proc/self/mounts
dd conv=fdatasync oflag=dsync if=/dev/zero of=fusemnt/tmp/tmp \
count=1K bs=1M 2>&1 | grep -v records
rm fusemnt/tmp/tmp
killall passthrough_fh
}
Test results:
passthrough_fh /tmp/fusemnt fuse.passthrough_fh \
rw,nosuid,nodev,relatime,user_id=0,group_id=0 0 0
1073741824 bytes (1.1 GB) copied, 1.73867 s, 618 MB/s
passthrough_fh /tmp/fusemnt fuse.passthrough_fh \
rw,nosuid,nodev,relatime,user_id=0,group_id=0,max_pages=256 0 0
1073741824 bytes (1.1 GB) copied, 1.15643 s, 928 MB/s
Obviously with bigger lag the difference between 'before' and 'after'
will be more significant.
Mitsuo Hayasaka, in 2012 (https://lkml.org/lkml/2012/7/5/136),
observed improvement from 400-550 to 520-740.
Signed-off-by: Constantine Shulyupin <const@MakeLinux.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Diffstat (limited to 'fs/fuse/dev.c')
| -rw-r--r-- | fs/fuse/dev.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index fefb9dd8a2f4..69d4df78a417 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -61,6 +61,7 @@ static struct fuse_req *__fuse_request_alloc(unsigned npages, gfp_t flags) struct page **pages = NULL; struct fuse_page_desc *page_descs = NULL; + WARN_ON(npages > FUSE_MAX_MAX_PAGES); if (npages > FUSE_REQ_INLINE_PAGES) { pages = kzalloc(npages * (sizeof(*pages) + sizeof(*page_descs)), flags); @@ -1674,7 +1675,7 @@ static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode, unsigned int num; unsigned int offset; size_t total_len = 0; - int num_pages; + unsigned int num_pages; offset = outarg->offset & ~PAGE_MASK; file_size = i_size_read(inode); @@ -1686,7 +1687,7 @@ static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode, num = file_size - outarg->offset; num_pages = (num + offset + PAGE_SIZE - 1) >> PAGE_SHIFT; - num_pages = min(num_pages, FUSE_MAX_PAGES_PER_REQ); + num_pages = min(num_pages, fc->max_pages); req = fuse_get_req(fc, num_pages); if (IS_ERR(req)) |