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HBase >> mail # user >> Lease does not exist exceptions


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Re: Lease does not exist exceptions
Perfect! Thanks.

-eran

On Thu, Oct 20, 2011 at 23:27, Jean-Daniel Cryans <[EMAIL PROTECTED]>wrote:

> hbase.regionserver.lease.period
>
> Set it bigger than 60000.
>
> J-D
>
> On Thu, Oct 20, 2011 at 2:23 PM, Eran Kutner <[EMAIL PROTECTED]> wrote:
> >
> > Thanks J-D!
> > Since my main table is expected to continue growing I guess at some point
> > even setting the cache size to 1 will not be enough. Is there a way to
> > configure the lease timeout?
> >
> > -eran
> >
> >
> >
> > On Thu, Oct 20, 2011 at 23:16, Jean-Daniel Cryans <[EMAIL PROTECTED]
> >wrote:
> >
> > > On Wed, Oct 19, 2011 at 12:51 PM, Eran Kutner <[EMAIL PROTECTED]> wrote:
> > >
> > > > Hi J-D,
> > > > Thanks for the detailed explanation.
> > > > So if I understand correctly the lease we're talking about is a
> scanner
> > > > lease and the timeout is between two scanner calls, correct? I think
> that
> > > > make sense because I now realize that jobs that fail (some jobs
> continued
> > > > to
> > > > fail even after reducing the number of map tasks as Stack suggested)
> use
> > > > filters to fetch relatively few rows out of a very large table, so
> they
> > > > could be spending a lot of time on the region server scanning rows
> until
> > > it
> > > > reached my setCaching value which was 1000. Setting the caching value
> to
> > > 1
> > > > seem to allow these job to complete.
> > > > I think it has to be the above, since my rows are small, with just a
> few
> > > > columns and processing them is very quick.
> > > >
> > >
> > > Excellent!
> > >
> > >
> > > >
> > > > However, there are still a couple ofw thing I don't understand:
> > > > 1. What is the difference between setCaching and setBatch?
> > > >
> > >
> > > * Set the maximum number of values to return for each call to next()
> > >
> > > VS
> > >
> > > * Set the number of rows for caching that will be passed to scanners.
> > >
> > > The former is useful if you have rows with millions of columns and you
> > > could
> > > setBatch to get only 1000 of them at a time. You could call that
> intra-row
> > > scanning.
> > >
> > >
> > > > 2. Examining the region server logs more closely than I did yesterday
> I
> > > see
> > > > a log of ClosedChannelExceptions in addition to the expired leases
> (but
> > > no
> > > > UnknownScannerException), is that expected? You can see an excerpt of
> the
> > > > log from one of the region servers here:
> http://pastebin.com/NLcZTzsY
> > >
> > >
> > > It means that when the server got to process that client request and
> > > started
> > > reading from the socket, the client was already gone. Killing a client
> does
> > > that (or killing a MR that scans), so does SocketTimeoutException. This
> > > should probably go in the book. We should also print something nicer :)
> > >
> > > J-D
> > >
>