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Date: Wed, 18 Feb 2009 11:23:37 +0100
Message-ID: <534ab810902180223t2fcd949ci8890911b19398556@mail.gmail.com>
Subject: Re: Improving hbase read performance
From: shourabh rawat <mirage1987@gmail.com>
To: hbase-user@hadoop.apache.org
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hey,

"> What do you mean by the above when you say read sequentially? Are you
> scanning? (Getting a scanner and then nexting through your hbase table?)."

well lets say i have 10 keys that are stored in hbase
i want to retrive them

If I do the reads one by one the time would be summation of  'get'
times of each key
Could i do the same thing in parallel. so that all the get's cld occur
concurrently so i would get total time as the max of the time taken by
any of these keys rather than the summ of individual times


"
> You will have to wait for hbase 0.20.0 or do as Erik suggests and put a
> cache in front of hbase.  What are you trying to do with hbase?  Serve a
> website? "

ya sort of but i want to check performance withought the use of cache
(random reads) ....can i get such performance in the range of 10 ms
with hbase

> Yeah, the RPC keeps a single connection per remote server but channel is
> shared by request and receive.  Testing in past, the more remote servers,
> the better, but even if a few only, concurrent HTables got better throughput
> than one running requests in series (the single connection is not fully
> occupied by requests and responses).
>

so by a single connection u mean all the gets wld be treated
sequentially (one by one) by the hbase even wen the requests come in
parallel(even wen different htable instances for the same table are
employed)....is there any way i can make it parallel.....
The hbase master has one port that it specifies and other is the port
for the hdfs (hadoop)....what can be done to increase the number of
connection as u said.......


Thanx for yr help.