For rejoining object, don't send lock ACK message because lock states
are still uncertain. The lock ACK may confuse object's auth MDS and
trigger assertion.
If object's auth MDS is not active, just skip sending NUDGE, REQRDLOCK
and REQSCATTER messages. MDCache::handle_mds_recovery() will take care
of them.
Also defer caps release message until clientreplay or active
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
The MDS may crash after journaling the new max size, but before sending
the new max size to the client. Later when the MDS recovers, the client
re-requests the new max size, but the MDS finds max size unchanged. So
the client waits for the new max size forever. This issue can be avoided
by checking client cap's last_sent, share inode max size if it is zero.
(reconnected cap's last_sent is zero)
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
For MDS cluster, not all file system namespace operations that impact
multiple MDS use two phase commit. Some operations use dentry link/unlink
message to update replica dentry's linkage after they are committed by
the master MDS. It's possible the master MDS crashes after journaling an
operation, but before sending the dentry link/unlink messages. Later when
the MDS recovers and receives cache rejoin messages from the surviving
MDS, it will find linkage mismatch.
The original cache rejoin code does not properly handle the case that
dentry unlink messages were missing. Unlinked inodes were linked to stray
dentries. So the cache rejoin ack message need push replicas of these
stray dentries to the surviving MDS.
This patch also adds code that handles cache expiration in the middle of
cache rejoining.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
Cache rejoin ack message already encodes inode base, make it also encode
dirfrag base. This allowes the message to replicate stray dentries like
MDentryUnlink message. The function will be used by later patch.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
So the recovering MDS can properly handle cache expire messages.
Also increase the nonce value when sending the cache rejoin acks.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
Also update the MMDSCacheRejoin encoding to the new format.
Signed-off-by: Greg Farnum <greg@inktank.com>
In commit 77946dcdae (mds: fetch missing inodes from disk), I introduced
MDCache::rejoin_fetch_dirfrags(). But it basicly duplicates the function
of MDCache::open_undef_dirfrags(), so just remove rejoin_fetch_dirfrags()
and make open_undef_dirfrags() also handle undefined inodes.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
For mds cluster, rename operation may involve multiple MDS. If the
rename source's auth MDS crashes after some witness MDS have prepared
the rename but before the rename is committing. Later when the MDS
recovers, its subtree map and linkages are different from the prepared
MDS'. This causes problems for both subtree resolve and cache rejoin.
The solution is, if the rename source's auth MDS fails, the prepared
witness MDS query the master MDS if the operation is committing. If
it's not, rollback the rename, then send resolve message to the
recovering MDS.
Another similar case is a prepared witness MDS crashes when the
rename source's auth MDS has prepared or is preparing the operation.
when the witness recovers, the master just delay sending the resolve
ack message until the it commits the operation.
This patch also updates Server::handle_client_rename(). Make preparing
the rename source's auth MDS be the final step before committing the
rename.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
The active MDS calls MDCache::rejoin_scour_survivor_replicas() when it
receives the cache rejoin message. The function will remove the objects
replicated by MDentry{Link,Unlink} from replica map.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
For active MDS, it may receive resolve/rejoin message before receiving
the mdsmap message that claims the MDS cluster is in resolving/rejoning
state. So instead of set the gather MDS set when receiving the mdsmap.
set them in advance when detecting MDS' failure.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
When MDS cluster is resolving, current behavior is sending subtree resolve
message to all other MDS and waiting for all other MDS' resolve message.
The problem is that active MDS can have diffent subtree map due to rename.
Besides gathering active MDS's resolve messages are also racy. The only
function for these messages is disambiguate other MDS' import. We can
replace it by import finish notification.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
Resolve messages for all MDS are the same, so we can compose and
send them in batch.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
Replicated objects need to be added into the cache immediately
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
When requesting remote xlock or remote wrlock, the master request is
put into lock object's REMOTEXLOCK waiting queue. The problem is that
remote wrlock's target can be different from lock's auth MDS. When
the lock's auth MDS recovers, MDCache::handle_mds_recovery() may wake
incorrect request. So just unify slave request waiting, dispatch the
master request when receiving slave request reply.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>
Locks' states should not change between composing the cache rejoin ack
messages and sending the message. If Locker::eval_gather() is called
in MDCache::{inode,dentry}_remove_replica(), it may wake requests and
change locks' states.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
When a MDS becomes active, the table server re-sends 'agree' messages
for old prepared request. If the recoverd MDS starts a new table request
at the same time, The new request's ID can happen to be the same as old
prepared request's ID, because current table client code assigns request
ID from zero after MDS restarts.
This patch make table server send 'ready' messages when table clients
become active or itself becomes active. The 'ready' message updates
table client's last_reqid to avoid request ID collision. The message
also replaces the roles of finish_recovery() and handle_mds_recovery()
callbacks for table client.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
MDS in clientreplsy state already starts servering requests. It also
make MDS::handle_mds_recovery() and MDS::recovery_done() match.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Greg Farnum <greg@inktank.com>
The signal method removes conds from the list after it signals. That's
not okay if the cond triggers for some other reason; an invalid Cond*
will remain on the list and get signaled later.
Make the wait_on_list() helper remove it; use that in several callers;
explicitly do the removal in the remaining callers.
Change signal_cond_list() to not clear the list; rely on the signalee's to
do that. Audit all users and make sure they are either using the
wait_on_list() helper (which removes its Cond) or do the remove explicitly.
Backport some form of this: bobtail
Signed-off-by: Sage Weil <sage@inktank.com>
discard, flush, and striping info slipped through the cracks before,
but are useful and trivial to add.
Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
The python interface is a bit awkward since it maps directly
to the C interface, but it'll work well enough and not use
tons of memory.
Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
All the other commands that display information have this.
For consistency, add it to this command too.
Also switch the plain output to use a TextTable for better readability.
Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
Without this, the same seed is used each time, so multiple runs
of bench-write with the same parameters have the same I/O pattern.
Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
Use int instead of bool for the callback, and make it represent
whether the data exists, rather than the opposite, since callers
are likely to test for whether it's data instead of whether its zeroes.
Change the return value to 0, since an int64_t will wrap around
for large reads, and there's no value in reporting the length
read when it will always be the length requested clipped to the
size of the image.
Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
safe_read() just protects against EINTR, and may return less data than
requested if it reaches the end of the file. Use safe_read_exact() to
make sure we get the right amount of data.
Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
This will be jumpy since changed extents probably aren't evenly
distributed, but it's better than nothing.
Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
