On Thu, Sep 13, 2012 at 9:51 AM, Jean-Daniel Cryans <[email protected]> wrote: > On Thu, Sep 13, 2012 at 9:42 AM, n keywal <[email protected]> wrote: >> It's all in the "pretty much" :-) >> Should we make it the default (i.e. recommending it in the doc, emitting a >> warning if it's not set) for all installation ? > > I'd recommend it in the doc as an important config to consider. > > One issue with the current implementation is that you can only have 1 > user that short circuit reads, all the others who have the config > enabled will get a fat Exception. At SU we don't have special config > files for every MR job so unless you disable it job by job then you'll > get those exceptions everywhere. We live with it but it did take > people by surprise when we rolled it out :) > >> Or would it make sense to separate the store and wal cases, meaning that we >> need a change in hdfs to make this possible? > > Don't we only have one FS instance per region server? If so, that's a > moot point. >
Write a short paragraph and I'll make an HDFS configuration sections like this HBase configurations section on manual and stick it in there: http://hbase.apache.org/book.html#perf.configurations St.Ack
