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authorJohn Spray <john.spray@redhat.com>2016-11-23 00:11:43 +0100
committerJohn Spray <john.spray@redhat.com>2016-11-23 00:14:14 +0100
commit3ae9bd840d3df0475af37baadc400b6d86c5e2b6 (patch)
tree636b308bb90e0819e8937357257f2735c8d021b2 /src/doc
parentsrc/doc: fix class names in exports.txt (diff)
downloadceph-3ae9bd840d3df0475af37baadc400b6d86c5e2b6.tar.xz
ceph-3ae9bd840d3df0475af37baadc400b6d86c5e2b6.zip
src/doc: remove anchortable.txt
The anchor table is long gone. Signed-off-by: John Spray <john.spray@redhat.com>
Diffstat (limited to 'src/doc')
-rw-r--r--src/doc/anchortable.txt54
1 files changed, 0 insertions, 54 deletions
diff --git a/src/doc/anchortable.txt b/src/doc/anchortable.txt
deleted file mode 100644
index d9c0fefc31e..00000000000
--- a/src/doc/anchortable.txt
+++ /dev/null
@@ -1,54 +0,0 @@
-
-ANCHOR TABLE PROTOCOL
-
-MDS sends an update PREPARE to the anchortable MDS. The prepare is
-identified by the ino and operation type; only one for each type
-(create, update, destroy) can be pending at any time. Both parties
-may actually be the same local node, but for simplicity we treat that
-situation the same. (That is, we act as if they may fail
-independently, even if they can't.)
-
-The anchortable journals the proposed update, and responds with an
-AGREE and a version number. This uniquely identifies the request.
-
-The MDS can then update the filesystem metadata however it sees fit.
-When it is finished (and the results journaled), it sends a COMMIT to
-the anchortable. The table journals the commit, frees any state from
-the transaction, and sends an ACK. The initiating MDS should then
-journal the ACK to complete the transaction.
-
-
-ANCHOR TABLE FAILURE
-
-If the AT fails before journaling the PREPARE and sending the AGREE,
-the initiating MDS will simply retry the request.
-
-If the AT fails after journaling PREPARE but before journaling COMMIT,
-it will resend AGREE to the initiating MDS.
-
-If the AT fails after the COMMIT, the transaction has been closed, and it
-takes no action. If it receives a COMMIT for which it has no open
-transaction, it will reply with ACK.
-
-
-INITIATING MDS FAILURE
-
-If the MDS fails before the metadata update has been journaled, no
-action is taken, since nothing is known about the previously proposed
-transaction. If an AGREE message is received and there is no
-corresponding PREPARE or pending-commit state, and ROLLBACK is sent to
-the anchor table.
-
-If the MDS fails after journaling the metadata update but before
-journaling the ACK, it resends COMMIT to the anchor table. If it
-receives an AGREE after resending the COMMIT, it simply ignores the
-AGREE. The anchortable will respond with an ACK, allowing the
-initiating MDS to journal the final ACK and close out the transaction
-locally.
-
-On journal replay, each metadata update (EMetaBlob) encountered that
-includes an anchor transaction is noted in the AnchorClient by adding
-it to the pending_commit list, and each journaled ACK is removed from
-that list. Journal replay may enounter ACKs with no prior metadata
-update; these are ignored. When recovery finishes, a COMMIT is sent
-for all outstanding transactions.