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HBase >> mail # user >> Scanner timeout -- any reason not to raise?


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Re: Scanner timeout -- any reason not to raise?
In 0.94, there is only one setting.
See release notes of HBASE-6170 which is in 0.95

Looks like this should help (in 0.95):

https://issues.apache.org/jira/browse/HBASE-2214
Do HBASE-1996 -- setting size to return in scan rather than count of rows
-- properly

>From your description, you should be able to raise the timeout since the
writes are relatively fast.

Cheers

On Wed, Mar 20, 2013 at 9:32 AM, Dan Crosta <[EMAIL PROTECTED]> wrote:

> I'm confused -- I only see one setting in CDH manager, what is the name of
> the other setting?
>
> Our load is moderately frequent small writes (in batches of 1000 cells at
> a time, typically split over a few hundred rows -- these complete very
> fast, we haven't seen any timeouts there), and infrequent batches of large
> reads (scans), which is where we do see timeouts. My guess is that the
> timeout is more due to our application taking some time -- apparently more
> than 60s -- to process the results of each scan's output, rather than due
> to slowness in HBase itself, which tends to be only moderately loaded
> (judging by CPU, network, and disk) while we do the reads.
>
> Thanks,
> - Dan
>
> On Mar 17, 2013, at 2:20 PM, Ted Yu wrote:
>
> > The lease timeout is used by row locking too.
> > That's the reason behind splitting the setting into two config
> parameters.
> >
> > How is your load composition ? Do you mostly serve reads from HBase ?
> >
> > Cheers
> >
> > On Sun, Mar 17, 2013 at 1:56 PM, Dan Crosta <[EMAIL PROTECTED]> wrote:
> >
> >> Ah, thanks Ted -- I was wondering what that setting was for.
> >>
> >> We are using CDH 4.2.0, which is HBase 0.94.2 (give or take a few
> >> backports from 0.94.3).
> >>
> >> Is there any harm in setting the lease timeout to something larger,
> like 5
> >> or 10 minutes?
> >>
> >> Thanks,
> >> - Dan
> >>
> >> On Mar 17, 2013, at 1:46 PM, Ted Yu wrote:
> >>
> >>> Which HBase version are you using ?
> >>>
> >>> In 0.94 and prior, the config param is hbase.regionserver.lease.period
> >>>
> >>> In 0.95, it is different. See release notes of HBASE-6170
> >>>
> >>> On Sun, Mar 17, 2013 at 11:46 AM, Dan Crosta <[EMAIL PROTECTED]> wrote:
> >>>
> >>>> We occasionally get scanner timeout errors such as "66698ms passed
> since
> >>>> the last invocation, timeout is currently set to 60000" when
> iterating a
> >>>> scanner through the Thrift API. Is there any reason not to raise the
> >>>> timeout to something larger than the default 60s? Put another way,
> what
> >>>> resources (and how much of them) does a scanner take up on a thrift
> >> server
> >>>> or region server?
> >>>>
> >>>> Also, to confirm -- I believe "hbase.rpc.timeout" is the setting in
> >>>> question here, but someone please correct me if I'm wrong.
> >>>>
> >>>> Thanks,
> >>>> - Dan
> >>>>
> >>>>
> >>>>
> >>
> >>
>
>