> On Jan. 22, 2014, 8:50 p.m., Bill Havanki wrote: > > src/server/src/main/java/org/apache/accumulo/server/Accumulo.java, line 226 > > <https://reviews.apache.org/r/17192/diff/1/?file=435500#file435500line226> > > > > I think the doubling of the sleep period in the last statement of the > > encompassing while loop will interfere here. The first time through, sleep > > will be set to TTL + 1 seconds (assuming it's set to something valid). The > > next time through, that sleep will have been doubled and will be selected > > for the next period instead of TTL + 1 again, because the doubled value is > > bigger. > > > > Also, the TTL value is a loop invariant so you could lift it out. > > Sean Busbey wrote: > is the interference from the doubling a problem? we just need to make > sure we don't ask for a host lookup and get a cached failure. Or should the > doubling not happen if we increased sleep based on this ttl, to avoid backing > off too far? > > any worry about the ttl changing between invocations by pulling it out of > the loop? It's not likely to change while running, but could. > > Sean Busbey wrote: > Actually, not invariant because the source of the underlying > UnknownHostException could change in the loop. Acceptable cost of > deduplicating the "your ttl is infinite" error handling talked about on > ACCUMULO-2224's review? > > Bill Havanki wrote: > The doubling isn't really a problem, but if we claim that we follow the > TTL, then as a user it would surprise me that we'd be doubling it between > checks. Documentation somewhere could cover it. > > I wouldn't care about the TTL changing between invocations. > > The TTL value is invariant, but the behavior of > getAddressCacheNegativeTtl isn't. This is where that refactoring creates a > problem. (Review for future reference is https://reviews.apache.org/r/17132). > I'm -0 on leaving it like it is.
do we claim to follow the TTL? I think this is just a matter of adjusting our back off window to make sure we aren't getting stale results. should the existing log message about sleeping specify that it's a back-off mechanism? something like log.info("Backing off due to failure. Current sleep window is " + sleep / 1000. + " seconds"); would that make it more understandable as the value increases? - Sean ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/17192/#review32532 ----------------------------------------------------------- On Jan. 22, 2014, 9:37 p.m., Sean Busbey wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/17192/ > ----------------------------------------------------------- > > (Updated Jan. 22, 2014, 9:37 p.m.) > > > Review request for accumulo and Bill Havanki. > > > Bugs: ACCUMULO-2225 > https://issues.apache.org/jira/browse/ACCUMULO-2225 > > > Repository: accumulo > > > Description > ------- > > ACCUMULO-2225 handle IllegalArgumentExceptions from Hadoop on host lookup > failure. > > Looks for cases where we treat IOExceptions out of Hadoop specially, then > attempts to replicate for UnknownHostExceptions that have been wrapped in > IllegalArgumentExceptions. > > > Diffs > ----- > > > src/core/src/main/java/org/apache/accumulo/core/client/ZooKeeperInstance.java > e02c19785c373170b2b0d47266a6988adeec7e17 > src/server/src/main/java/org/apache/accumulo/server/Accumulo.java > 253962bca5f2573fdfa87b82e145938e190842ed > > src/server/src/main/java/org/apache/accumulo/server/master/tableOps/DeleteTable.java > 1c4d4ad8af30350d93f6dcfe2291463a90c835d3 > > src/server/src/main/java/org/apache/accumulo/server/tabletserver/Compactor.java > 29b8455a2dce5ecf2195d9704980e3e9749683f4 > > src/server/src/main/java/org/apache/accumulo/server/test/randomwalk/security/SecurityHelper.java > c8d1ea0872564643342387373d85b5ac87a57540 > > src/server/src/main/java/org/apache/accumulo/server/util/TabletOperations.java > 4a39050a17f84293c52f09b62932be5b957c8a91 > > Diff: https://reviews.apache.org/r/17192/diff/ > > > Testing > ------- > > builds on both hadoop profiles. starting functional tests now in combination > with 17132 > > > Thanks, > > Sean Busbey > >