If I have a workload where the access pattern is writing to and reading from the same row, does it make sense to turn the blockcache off? In other words, reads and writes to a given row always go together. Does each write cause eviction of the cached block(s) that the row is stored in? I would think so, but I couldn't find an answer to this anywhere online.
bq. Does each write cause eviction of the cached block(s)
Write first goes to memstore. If you read the same row immediately after write, the read request would be served by memstore - if flush hasn't happened. On Fri, Mar 28, 2014 at 2:23 PM, Rendon, Carlos (KBB) <[EMAIL PROTECTED]>wrote:
What is your blockcache hit rate like? Are your gets totally random across the namespace or is there any locality at all? Can you try turning it off on one of your regionservers and see how it does? Why you want to turn off the block cache, just because it is not being used? There are also these set of configs to try: http://hbase.apache.org/xref/org/apache/hadoop/hbase/io/hfile/CacheConfig.html#40 If locality of requests, the cache on write might help?
St.Ack On Fri, Mar 28, 2014 at 2:23 PM, Rendon, Carlos (KBB) <[EMAIL PROTECTED]>wrote:
On Mon, Mar 31, 2014 at 4:06 PM, Rendon, Carlos (KBB) <[EMAIL PROTECTED]>wrote: That is correct. BlockCache is by the server currently. There are no per-table nor per-cf configs though fellas have been asking for them...
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