replies inline.
stack wrote:
What Jim said and then....
For sure you are not creating a new HTable per request?
No I am not. The table is created upfront and records inserted using
a map/reduce job. This is for reads only.
How many regions in your table?
2.
Which version of HBase?
hbase-0.1.
Why do you have Tomcat in the picture? Because clients are doing HTTP?
Yes. the clients are doing http requests only. I also tested using
the rest api for random reads. Similar benchmarks were obtained.
The time for sure is being spent making the request out to HBase
and not spent transforming HBase results in and out of HTTP?
That is something I have to check again. But given that each
record has just one column and the value size does not exceed 5k, it
should not be an issue i guess.
thanks
karthik
Thanks,
St.Ack
Karthik Pattabiraman wrote:
Hi,
I am evaluating HBase for a serving system. The requirements are
fairly simple. Each record comprises a key and a value (size ~4k).
I set up a small cluster consisting of two boxes and the number of
records inserted into the table is close to 65K.
Now I ran a tomcat server on one of the boxes (where the master is
running). The tomcat server establishes a connection to hbase at
start and then on each request queries the hbase for the record.
The benchmarks were not good. I ran the benchmarks for 30 min with
20 clients (talking to tomcat) and the average response time was 51
ms. When I increased the number of clients to 50, the average
response time increased to 110 ms. To ensure that tomcat is not the
bottleneck, I logged the time taken for each Hbase request and found
that to be correlating the benchmarks (time increased when i
increased the number of clients.).
Any idea as to why this would happen given that the number of
records is not huge? (FYI: Both the boxes act as region servers, the
box where tomcat runs, also runs hbase master and the dfs namenode)
Could it be due to the way I have set up Hbase?
Any help would be appreciated.
thanks
karthik
