hbase-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From ChingShen <chingshenc...@gmail.com>
Subject Re: The hfile.block.cache.size = 0 performance is better than default(0.2) in random read? Is it possible?
Date Thu, 21 Oct 2010 06:18:08 GMT
Yes, only 14.7% :-(

2010-10-21 10:59:06,675 DEBUG
org.apache.hadoop.hbase.io.hfile.LruBlockCache: Cache Stats: Sizes:
Total=572.39557MB (600200272), Free=125.94194MB (132059696), Max=698.3375MB
(732259968), Counts: Blocks=8992, Access=235641, Hit=34786, Miss=200855,
Evictions=173, Evicted=191863, Ratios: *Hit  Ratio=14.762286841869354**%*,
Miss Ratio=85.23771166801453%, Evicted/Run=1109.03466796875

I agree much better performance with more cache, because that can improve
the hit ratio in random read, but I want to know why I disabled block cache
and got better throughput than default?

2010/10/21 Antonio Alvarado Hernández <aalvaradoh@gmail.com>

> Hi all,
> Could be related with a low hit ratio?
> -aah
>
>

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