| Message ID | 20150520141301.GA16249@ret.masoncoding.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Wed, May 20, 2015 at 10:13:11AM -0400, Chris Mason wrote: > Commit 2f0810880f082fa8ba66ab2c33b02e4ff9770a5e changed > btrfs_set_block_group_ro to avoid trying to allocate new chunks with the > new raid profile during conversion. This fixed failures when there was > no space on the drive to allocate a new chunk, but the metadata > reserves were sufficient to continue the conversion. > > But this ended up causing a regression when the drive had plenty of > space to allocate new chunks, mostly because reduce_alloc_profile isn't > using the new raid profile. > > Fixing btrfs_reduce_alloc_profile is a bigger patch. For now, do a > partial revert of 2f0810880, and don't error out if we hit ENOSPC. > > Signed-off-by: Chris Mason <clm@fb.com> > --- > fs/btrfs/extent-tree.c | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c > index 45e3f08..a115599 100644 > --- a/fs/btrfs/extent-tree.c > +++ b/fs/btrfs/extent-tree.c > @@ -8829,6 +8829,26 @@ again: > goto again; > } > > + /* > + * if we are changing raid levels, try to allocate a corresponding > + * block group with the new raid level. > + */ > + if (!(cache->flags & BTRFS_BLOCK_GROUP_SYSTEM)) { This prevents to switch the system chunk in all cases. What was the reason to do it? If I remove the check, then the conversions work in all combinations. Eg. * convert from ext (or use any single device fs) * add second device * balance data/metadata/system to raid1 * all fine -- 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
On 05/20/2015 01:02 PM, David Sterba wrote: > On Wed, May 20, 2015 at 10:13:11AM -0400, Chris Mason wrote: >> Commit 2f0810880f082fa8ba66ab2c33b02e4ff9770a5e changed >> btrfs_set_block_group_ro to avoid trying to allocate new chunks with the >> new raid profile during conversion. This fixed failures when there was >> no space on the drive to allocate a new chunk, but the metadata >> reserves were sufficient to continue the conversion. >> >> But this ended up causing a regression when the drive had plenty of >> space to allocate new chunks, mostly because reduce_alloc_profile isn't >> using the new raid profile. >> >> Fixing btrfs_reduce_alloc_profile is a bigger patch. For now, do a >> partial revert of 2f0810880, and don't error out if we hit ENOSPC. >> >> Signed-off-by: Chris Mason <clm@fb.com> >> --- >> fs/btrfs/extent-tree.c | 20 ++++++++++++++++++++ >> 1 file changed, 20 insertions(+) >> >> diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c >> index 45e3f08..a115599 100644 >> --- a/fs/btrfs/extent-tree.c >> +++ b/fs/btrfs/extent-tree.c >> @@ -8829,6 +8829,26 @@ again: >> goto again; >> } >> >> + /* >> + * if we are changing raid levels, try to allocate a corresponding >> + * block group with the new raid level. >> + */ >> + if (!(cache->flags & BTRFS_BLOCK_GROUP_SYSTEM)) { > > This prevents to switch the system chunk in all cases. What was the > reason to do it? I thought the system chunk was being caught by check_system_chunk below, but no, its using the wrong profile. It did work when I tested, but I ran it a few times in a row and got inconsistent results. > > If I remove the check, then the conversions work in all combinations. > Eg. Thanks, I'm pushing out an updated patch without the check. -chris -- 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
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 45e3f08..a115599 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -8829,6 +8829,26 @@ again: goto again; } + /* + * if we are changing raid levels, try to allocate a corresponding + * block group with the new raid level. + */ + if (!(cache->flags & BTRFS_BLOCK_GROUP_SYSTEM)) { + alloc_flags = update_block_group_flags(root, cache->flags); + if (alloc_flags != cache->flags) { + ret = do_chunk_alloc(trans, root, alloc_flags, + CHUNK_ALLOC_FORCE); + /* + * ENOSPC is allowed here, we may have enough space + * already allocated at the new raid level to + * carry on + */ + if (ret == -ENOSPC) + ret = 0; + if (ret < 0) + goto out; + } + } ret = set_block_group_ro(cache, 0); if (!ret)
Commit 2f0810880f082fa8ba66ab2c33b02e4ff9770a5e changed btrfs_set_block_group_ro to avoid trying to allocate new chunks with the new raid profile during conversion. This fixed failures when there was no space on the drive to allocate a new chunk, but the metadata reserves were sufficient to continue the conversion. But this ended up causing a regression when the drive had plenty of space to allocate new chunks, mostly because reduce_alloc_profile isn't using the new raid profile. Fixing btrfs_reduce_alloc_profile is a bigger patch. For now, do a partial revert of 2f0810880, and don't error out if we hit ENOSPC. Signed-off-by: Chris Mason <clm@fb.com> --- fs/btrfs/extent-tree.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+)