Adar Dembo has posted comments on this change. Change subject: log block manager: use extent maps to decide whether to truncate containers ......................................................................
Patch Set 6: > Yea, I think it's quite reasonable to only do so in a "fs check > --repair" type situation. OK, I'll work on that. > Another option I think is reasonable is to use stat() on the > container file, see the actual space usage, and if it's > significantly more than we expect based on the live block count in > the container, trigger the hole-punching. Right, we talked about this before. Assuming an "expensive repair" thing exists, the issue isn't knowing _when_ to re-hole-punch; it's knowing _how much_ unpunched space exists (for reporting purposes), and this approach doesn't provide an accurate measure of that. > A third option: when we successfully hole-punch after a delete, > write an entry to the metadata file saying "hole-punched!" (no need > to fsync it). On restart, re-punch any containers which have > deletions at the trail of the metadata with no "hole-punched!". > This way you'd only have to re-punch those files which might have > missed their chance due to a premature process exit last time > around. That's an interesting idea, though it trades off extent map fetching for larger metadata files. Need to think more about it. > BTW the restart times are longer than i expected, would be curious > to know where all that time is going (but that's unrelated to this > jira) I'll look into that later. -- To view, visit http://gerrit.cloudera.org:8080/6585 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: comment Gerrit-Change-Id: I3541f70721328d5af911f4889f8b4bcf0de3ebf8 Gerrit-PatchSet: 6 Gerrit-Project: kudu Gerrit-Branch: master Gerrit-Owner: Adar Dembo <a...@cloudera.com> Gerrit-Reviewer: Adar Dembo <a...@cloudera.com> Gerrit-Reviewer: David Ribeiro Alves <dral...@apache.org> Gerrit-Reviewer: Kudu Jenkins Gerrit-Reviewer: Todd Lipcon <t...@apache.org> Gerrit-HasComments: No
