On Wed, Aug 8, 2012 at 3:46 PM, Russell Blau <russb...@imapmail.org> wrote: > There is a possible workaround. The TS could treat this like a server > outage; copy user databases from thyme to rosemary and then point > sql-s1-user to rosemary, which currently has no replag. Rosemary would > then have to handle twice the load, but thyme should start to recover > very quickly with no user-generated queries hitting it. Once thyme has > recovered, point sql-s1-rr to it. > > Downsides: (1) this would require several hours of downtime for > sql-s1-user while the user databases are copied; all tools that require > access to user databases would be offline entirely for this period. (2) > it would have to wait until our volunteer TS admins have time to do it. Actually, it could probably be reduced from "downtime" to "readonly user databases". If thyme were writing at the binlog, it could probably stay accepting writes for the most part of it. This comes at the expense of TS admin time, of course.
> (3) the added load on rosemary could cause replag to grow there, > although I doubt it would come anywhere near the 14+ days replag we are > dealing with now on thyme. Depending on the insert speed without queries, another option would be the time needed for copying the db from rosemary to thyme. (I'm assuming it would be much slower than the downtime moving user dbs but it's just a guess, if it weren't this could replace that move). _______________________________________________ Toolserver-l mailing list (Toolserver-l@lists.wikimedia.org) https://lists.wikimedia.org/mailman/listinfo/toolserver-l Posting guidelines for this list: https://wiki.toolserver.org/view/Mailing_list_etiquette
