hbase-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From stack <st...@duboce.net>
Subject Re: Scanner Performance Question / Observation
Date Mon, 03 Aug 2009 22:34:00 GMT
On Mon, Aug 3, 2009 at 1:58 PM, Xinan Wu <wuxinan@gmail.com> wrote:

> 6 sec isn't crazy with 0.19. If you really want to research it, have a
> look at where the time is spent, creating scanner or actually doing
> the scanning. I think it's the former.


You are probably right that it is the fomer.  In 0.19, scanners would open a
new Reader against every file in the region before scanning could start
(trip to namenode, then out to each dn to read in indices, etc.).  In
0.20.0, the already-open files are used.
St.Ack

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