[
https://issues.apache.org/jira/browse/HBASE-7404?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
chunhui shen updated HBASE-7404:
--------------------------------
Description:
First, thanks @neil from Fusion-IO share the source code.
Usage:
1.Use bucket cache as a mainly memory cache, configure as the following:
–"hbase.bucketcache.ioengine" "heap"
–"hbase.bucketcache.size" 0.4 (size for bucket cache, 0.4 is a percentage of
max heap size)
2.Use bucket cache as a secondary cache, configure as the following:
–"hbase.bucketcache.ioengine" "file:/disk1/hbase/cache.data"(The file path
where to store the block data)
–"hbase.bucketcache.size" 1024 (size for bucket cache, unit is MB, so 1024
means 1GB)
–"hbase.bucketcache.combinedcache.enabled" false
See more configurations from org.apache.hadoop.hbase.io.hfile.CacheConfig and
org.apache.hadoop.hbase.io.hfile.bucket.BucketCache
What's Bucket Cache?
It could greatly decrease CMS and heap fragment by GC
It support a large cache space for High Read Performance by using high speed
disk like Fusion-io
1.An implementation of block cache like LruBlockCache
2.Self manage blocks' storage position through Bucket Allocator
3.The cached blocks could be stored in the memory or file system
4.Bucket Cache could be used as a mainly block cache(see CombinedBlockCache),
combined with LruBlockCache to decrease CMS and fragment by GC.
5.BucketCache also could be used as a secondary cache(e.g. using Fusionio to
store block) to enlarge cache space
How about SlabCache?
We have studied and test SlabCache first, but the result is bad, because:
1.SlabCache use SingleSizeCache, its use ratio of memory is low because kinds
of block size, especially using DataBlockEncoding
2.SlabCache is uesd in DoubleBlockCache, block is cached both in SlabCache and
LruBlockCache, put the block to LruBlockCache again if hit in SlabCache , it
causes CMS and heap fragment don't get any better
3.Direct heap performance is not good as heap, and maybe cause OOM, so we
recommend using "heap" engine
See more in the attachment and in the patch
was:
First, thanks @neil from Fusion-IO share the source code.
What's Bucket Cache?
It could greatly decrease CMS and heap fragment by GC
It support a large cache space for High Read Performance by using high speed
disk like Fusion-io
1.An implementation of block cache like LruBlockCache
2.Self manage blocks' storage position through Bucket Allocator
3.The cached blocks could be stored in the memory or file system
4.Bucket Cache could be used as a mainly block cache(see CombinedBlockCache),
combined with LruBlockCache to decrease CMS and fragment by GC.
5.BucketCache also could be used as a secondary cache(e.g. using Fusionio to
store block) to enlarge cache space
How about SlabCache?
We have studied and test SlabCache first, but the result is bad, because:
1.SlabCache use SingleSizeCache, its use ratio of memory is low because kinds
of block size, especially using DataBlockEncoding
2.SlabCache is uesd in DoubleBlockCache, block is cached both in SlabCache and
LruBlockCache, put the block to LruBlockCache again if hit in SlabCache , it
causes CMS and heap fragment don't get any better
3.Direct heap performance is not good as heap, and maybe cause OOM, so we
recommend using "heap" engine
See more in the attachment and in the patch
> Bucket Cache:A solution about CMS,Heap Fragment and Big Cache on HBASE
> ----------------------------------------------------------------------
>
> Key: HBASE-7404
> URL: https://issues.apache.org/jira/browse/HBASE-7404
> Project: HBase
> Issue Type: New Feature
> Affects Versions: 0.94.3
> Reporter: chunhui shen
> Assignee: chunhui shen
> Fix For: 0.96.0, 0.94.5
>
> Attachments: 7404-trunk-v10.patch, 7404-trunk-v11.patch,
> 7404-trunk-v12.patch, 7404-trunk-v13.patch, 7404-trunk-v13.txt,
> 7404-trunk-v14.patch, BucketCache.pdf, hbase-7404-94v2.patch,
> hbase-7404-trunkv2.patch, hbase-7404-trunkv9.patch, Introduction of Bucket
> Cache.pdf
>
>
> First, thanks @neil from Fusion-IO share the source code.
> Usage:
> 1.Use bucket cache as a mainly memory cache, configure as the following:
> –"hbase.bucketcache.ioengine" "heap"
> –"hbase.bucketcache.size" 0.4 (size for bucket cache, 0.4 is a percentage of
> max heap size)
> 2.Use bucket cache as a secondary cache, configure as the following:
> –"hbase.bucketcache.ioengine" "file:/disk1/hbase/cache.data"(The file path
> where to store the block data)
> –"hbase.bucketcache.size" 1024 (size for bucket cache, unit is MB, so 1024
> means 1GB)
> –"hbase.bucketcache.combinedcache.enabled" false
> See more configurations from org.apache.hadoop.hbase.io.hfile.CacheConfig and
> org.apache.hadoop.hbase.io.hfile.bucket.BucketCache
> What's Bucket Cache?
> It could greatly decrease CMS and heap fragment by GC
> It support a large cache space for High Read Performance by using high speed
> disk like Fusion-io
> 1.An implementation of block cache like LruBlockCache
> 2.Self manage blocks' storage position through Bucket Allocator
> 3.The cached blocks could be stored in the memory or file system
> 4.Bucket Cache could be used as a mainly block cache(see CombinedBlockCache),
> combined with LruBlockCache to decrease CMS and fragment by GC.
> 5.BucketCache also could be used as a secondary cache(e.g. using Fusionio to
> store block) to enlarge cache space
> How about SlabCache?
> We have studied and test SlabCache first, but the result is bad, because:
> 1.SlabCache use SingleSizeCache, its use ratio of memory is low because kinds
> of block size, especially using DataBlockEncoding
> 2.SlabCache is uesd in DoubleBlockCache, block is cached both in SlabCache
> and LruBlockCache, put the block to LruBlockCache again if hit in SlabCache ,
> it causes CMS and heap fragment don't get any better
> 3.Direct heap performance is not good as heap, and maybe cause OOM, so we
> recommend using "heap" engine
> See more in the attachment and in the patch
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
