GEODE-3801: Use hardlinks for backup oplog files #963
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
* Oplog files that are backed up are read-only. For this reason,
they can be transfered to the backup location through hard links,
instead of copying the file. This change improves speed of backups.
If the creation of a hard link fails, we revert to the existing copy
behavior.
* During backups, the copying of the oplog's krf file was being done while
that file could still be in the process of writing. This change ensures
that if a krf is to be written, that it is finished and included in the
backup
* cleanup existing oplog tests
nreich
requested review from
agingade,
dschneider-pivotal,
kirklund,
lgallinat and
pivotal-eshu
kirklund
requested changes
Oct 20, 2017
Contributor
kirklund
left a comment
kirklund
left a comment
There was a problem hiding this comment.
Everything looks good to me except the one log statement I commented on.
| try { | ||
| Files.createLink(targetDir.toPath().resolve(file.getName()), file.toPath()); | ||
| } catch (IOException | UnsupportedOperationException e) { | ||
| logger.warn("Unable to create hard link for + " + targetDir + ". Reverting to file copy"); |
Contributor
There was a problem hiding this comment.
You have an extra + after inside the log statement quotes.
The Log4J2 way is to use their parameters:
logger.warn("Unable to create hard link for {}. Reverting to file copy", targetDir);
| private void backupFile(File targetDir, File file) throws IOException { | ||
| if (file != null && file.exists()) | ||
| try { | ||
| Files.createLink(targetDir.toPath().resolve(file.getName()), file.toPath()); |
Contributor
There was a problem hiding this comment.
Is there any reason you cannot use a symbolic link here? That way it would allow the link to span filesystems too.
Author
There was a problem hiding this comment.
The use of a hard link here is to replace the existing logic of making a copy of the original file for the backup. Deletion of the original file cannot be allowed to result in loss of that file in the backup location and thus a symbolic link cannot be used in this case. Hard links can be used here in place of copying the file only because the Oplog files being copied are guaranteed to be read-only.
Contributor
There was a problem hiding this comment.
OK - that makes sense. Thanks for the explanation.
dschneider-pivotal
approved these changes
Oct 23, 2017
kirklund
added a commit
to kirklund/geode
that referenced
this pull request
Nov 2, 2017
…pache#963)" This reverts commit 6a4e50e. The revision is causing a hang in Backup which is filed as GEODE-3940.
kirklund
added a commit
to kirklund/geode
that referenced
this pull request
Nov 3, 2017
…pache#963)" This reverts commit 6a4e50e. The revision is causing a hang in Backup which is filed as GEODE-3940.
kirklund
pushed a commit
that referenced
this pull request
Nov 6, 2017
* Oplog files that are backed up are read-only. For this reason, they can be transfered to the backup location through hard links, instead of copying the file. This change improves speed of backups. If the creation of a hard link fails, we revert to the existing copy behavior. * During backups, the copying of the oplog's krf file was being done while that file could still be in the process of writing. This change ensures that if a krf is to be written, that it is finished and included in the backup * cleanup existing oplog tests
kirklund
pushed a commit
that referenced
this pull request
Nov 7, 2017
* Oplog files that are backed up are read-only. For this reason, they can be transfered to the backup location through hard links, instead of copying the file. This change improves speed of backups. If the creation of a hard link fails, we revert to the existing copy behavior. * During backups, the copying of the oplog's krf file was being done while that file could still be in the process of writing. This change ensures that if a krf is to be written, that it is finished and included in the backup * cleanup existing oplog tests
smgoller
pushed a commit
to smgoller/geode
that referenced
this pull request
Nov 13, 2017
…pache#963)" This reverts commit 6a4e50e. The revision is causing a hang in Backup which is filed as GEODE-3940.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
5 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
they can be transfered to the backup location through hard links,
instead of copying the file. This change improves speed of backups.
If the creation of a hard link fails, we revert to the existing copy
behavior.
that file could still be in the process of writing. This change ensures
that if a krf is to be written, that it is finished and included in the
backup