hbase-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Ted Yu <yuzhih...@gmail.com>
Subject Re: hbase:meta blocks in L1?
Date Fri, 15 Jul 2016 00:08:26 GMT
I looked at related code in branch-1.
HColumnDescriptor#isCacheDataInL1() uses default value of
HColumnDescriptor.DEFAULT_CACHE_DATA_IN_L1 which is false

I think setCacheDataInL1(true) call is needed for meta HTableDescriptor

On Thu, Jul 14, 2016 at 12:57 PM, Nick Dimiduk <ndimiduk@gmail.com> wrote:

> IIRC, the configuration handling and IoC of multi-level block cache changed
> significantly around 1.2. This was to facilitate an overhaul and overall
> improvement of how cache layers are built, defined, and configured.
> Structures may be quite different between master and various incarnations
> of 1.x branches. Please examine each independently, don't assume what holds
> on one branch applies to another.
>
> On Thu, Jul 14, 2016 at 12:35 PM, Ted Yu <yuzhihong@gmail.com> wrote:
>
> > Interesting.
> >
> > Do you want to log a JIRA ?
> >
> > I checked HTableDescriptor.java in branch-1.1 to branch-1 where
> > setCacheDataInL1(true) is missing.
> >
> > The fix would be a one line change.
> >
> > On Thu, Jul 14, 2016 at 11:43 AM, Lars George <lars.george@gmail.com>
> > wrote:
> >
> > > Ah wait, this was fixed in
> > > https://issues.apache.org/jira/browse/HBASE-15467, but is not right
> > > (if I read this proper) in the 1.x line. It could mean that hbase:meta
> > > is cached in L2 only.
> > >
> > > On Thu, Jul 14, 2016 at 7:37 PM, Ted Yu <yuzhihong@gmail.com> wrote:
> > > > Looking at FSTableDescriptors#createMetaTableDescriptor() , both
> column
> > > > families have the following:
> > > >
> > > >                 .setCacheDataInL1(true),
> > > >
> > > > Is there something else you were looking for ?
> > > >
> > > > Cheers
> > > >
> > > > On Thu, Jul 14, 2016 at 6:59 AM, Lars George <lars.george@gmail.com>
> > > wrote:
> > > >
> > > >> Hey,
> > > >>
> > > >> HBASE-11364 did add `.setCacheDataInL1(true)`, but the later change
> to
> > > >> use `HTableDescriptor.metaTableDescriptor()` changes the layout of
> the
> > > >> `hbase:meta` to omit the L1 cache setting. Is this on purpose or an
> > > >> oversight?
> > > >>
> > > >> In other words, are the meta blocks currently never cached in L1?
> > > >>
> > > >> Lars
> > > >>
> > >
> >
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message