| Message ID | 1319824917-28345-1-git-send-email-gharm@google.com |
|---|---|
| State | Superseded, archived |
| Headers | show |
On 2011-10-28, at 12:01 PM, Greg Harm <gharm@google.com> wrote: > If an fallocate request fits in EXT_UNINIT_MAX_LEN, then set the > EXT4_GET_BLOCKS_NO_NORMALIZE flag. For larger fallocate requests, > let mballoc.c normalize the request. > This fixes a problem where large requests were being split > into non-contiguous extents due to haldar@google.com's > "ext4: do not normalize block requests from fallocate." > > Testing: Checked that 8.x MB falloc'ed files are still laid down > next to each other (contiguously). > Checked that the maximum size extent (127.9MB) is allocated as 1 > extent. > Checked that a 1GB file is somewhat contiguous (often 5-6 > non-contiguous extents now). > Checked that a 120MB file can still be falloc'ed even if there are no > single extents large enough to hold it. It would be great to add these test cases to xfstests so that this doesn't break in the future. > Signed-off-by: Greg Harm <gharm@google.com> > --- > fs/ext4/extents.c | 13 ++++++++++--- > 1 files changed, 10 insertions(+), 3 deletions(-) > > diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c > index 57cf568..9819216 100644 > --- a/fs/ext4/extents.c > +++ b/fs/ext4/extents.c > @@ -3761,6 +3761,7 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len) > int ret2 = 0; > int retries = 0; > struct ext4_map_blocks map; > + int map_blocks_flags; > unsigned int credits, blkbits = inode->i_blkbits; > > /* > @@ -3805,9 +3806,15 @@ retry: > ret = PTR_ERR(handle); > break; > } > - ret = ext4_map_blocks(handle, inode, &map, > - EXT4_GET_BLOCKS_CREATE_UNINIT_EXT | > - EXT4_GET_BLOCKS_NO_NORMALIZE); > + map_blocks_flags = EXT4_GET_BLOCKS_CREATE_UNINIT_EXT; > + /* > + * Don't normalize the request if it can fit in one extent so > + * that it doesn't get unnecessarily split into multiple > + * extents. > + */ > + if (len <= EXT_UNINIT_MAX_LEN << blkbits) > + map_blocks_flags |= EXT4_GET_BLOCKS_NO_NORMALIZE; > + ret = ext4_map_blocks(handle, inode, &map, map_blocks_flags); > if (ret <= 0) { > #ifdef EXT4FS_DEBUG > WARN_ON(ret <= 0); > -- > 1.7.3.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Oct 28, 2011 at 11:47 AM, Andreas Dilger <aedilger@gmail.com> wrote: > On 2011-10-28, at 12:01 PM, Greg Harm <gharm@google.com> wrote: >> If an fallocate request fits in EXT_UNINIT_MAX_LEN, then set the >> EXT4_GET_BLOCKS_NO_NORMALIZE flag. For larger fallocate requests, >> let mballoc.c normalize the request. >> This fixes a problem where large requests were being split >> into non-contiguous extents due to haldar@google.com's >> "ext4: do not normalize block requests from fallocate." >> >> Testing: Checked that 8.x MB falloc'ed files are still laid down >> next to each other (contiguously). >> Checked that the maximum size extent (127.9MB) is allocated as 1 >> extent. >> Checked that a 1GB file is somewhat contiguous (often 5-6 >> non-contiguous extents now). >> Checked that a 120MB file can still be falloc'ed even if there are no >> single extents large enough to hold it. > > It would be great to add these test cases to xfstests so that this doesn't break in the future. Hi Andreas, I totally agree. I have that on my TODO list (but no current ETA). Thanks, Greg >> Signed-off-by: Greg Harm <gharm@google.com> >> --- >> fs/ext4/extents.c | 13 ++++++++++--- >> 1 files changed, 10 insertions(+), 3 deletions(-) >> >> diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c >> index 57cf568..9819216 100644 >> --- a/fs/ext4/extents.c >> +++ b/fs/ext4/extents.c >> @@ -3761,6 +3761,7 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len) >> int ret2 = 0; >> int retries = 0; >> struct ext4_map_blocks map; >> + int map_blocks_flags; >> unsigned int credits, blkbits = inode->i_blkbits; >> >> /* >> @@ -3805,9 +3806,15 @@ retry: >> ret = PTR_ERR(handle); >> break; >> } >> - ret = ext4_map_blocks(handle, inode, &map, >> - EXT4_GET_BLOCKS_CREATE_UNINIT_EXT | >> - EXT4_GET_BLOCKS_NO_NORMALIZE); >> + map_blocks_flags = EXT4_GET_BLOCKS_CREATE_UNINIT_EXT; >> + /* >> + * Don't normalize the request if it can fit in one extent so >> + * that it doesn't get unnecessarily split into multiple >> + * extents. >> + */ >> + if (len <= EXT_UNINIT_MAX_LEN << blkbits) >> + map_blocks_flags |= EXT4_GET_BLOCKS_NO_NORMALIZE; >> + ret = ext4_map_blocks(handle, inode, &map, map_blocks_flags); >> if (ret <= 0) { >> #ifdef EXT4FS_DEBUG >> WARN_ON(ret <= 0); >> -- >> 1.7.3.1 >> > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 57cf568..9819216 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -3761,6 +3761,7 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len) int ret2 = 0; int retries = 0; struct ext4_map_blocks map; + int map_blocks_flags; unsigned int credits, blkbits = inode->i_blkbits; /* @@ -3805,9 +3806,15 @@ retry: ret = PTR_ERR(handle); break; } - ret = ext4_map_blocks(handle, inode, &map, - EXT4_GET_BLOCKS_CREATE_UNINIT_EXT | - EXT4_GET_BLOCKS_NO_NORMALIZE); + map_blocks_flags = EXT4_GET_BLOCKS_CREATE_UNINIT_EXT; + /* + * Don't normalize the request if it can fit in one extent so + * that it doesn't get unnecessarily split into multiple + * extents. + */ + if (len <= EXT_UNINIT_MAX_LEN << blkbits) + map_blocks_flags |= EXT4_GET_BLOCKS_NO_NORMALIZE; + ret = ext4_map_blocks(handle, inode, &map, map_blocks_flags); if (ret <= 0) { #ifdef EXT4FS_DEBUG WARN_ON(ret <= 0);
If an fallocate request fits in EXT_UNINIT_MAX_LEN, then set the EXT4_GET_BLOCKS_NO_NORMALIZE flag. For larger fallocate requests, let mballoc.c normalize the request. This fixes a problem where large requests were being split into non-contiguous extents due to haldar@google.com's "ext4: do not normalize block requests from fallocate." Testing: Checked that 8.x MB falloc'ed files are still laid down next to each other (contiguously). Checked that the maximum size extent (127.9MB) is allocated as 1 extent. Checked that a 1GB file is somewhat contiguous (often 5-6 non-contiguous extents now). Checked that a 120MB file can still be falloc'ed even if there are no single extents large enough to hold it. Signed-off-by: Greg Harm <gharm@google.com> --- fs/ext4/extents.c | 13 ++++++++++--- 1 files changed, 10 insertions(+), 3 deletions(-)