Raymond Raymond wrote:
>> I ran a variant of the TPC-B benchmark with a large database (20 GB)
>> and a large page cache (1 GB). I do not think you need TPC-B
>> transactions to see this, but I think you need update-intensive
>> transactions that frequently needs to load pages from disk. For
>> example, single record updates where an index is used to locate the
>> record. You will also need several connections in parallel (e.g., 20).
>>
>> --
>> Øystein
>
> Thanks for your answer. Did you use some tools to know something like
> "single write operations that took almost 12 seconds" and "read requests
> that took more than 20 seconds". I downloaded TPC-B benchmark program,
> it didn't give me those kind of information. I want to know how did you
> know the time for reads and writes.^_^.
>
No special tools. Our TPCB-client writes the number of committed
transaction for each 10 second interval. That way, I observed regular
drops in throughput. I/O response times was measured by instrumenting
RAFContainer to measure the time it takes to do seek and read/write.
This was written to derby.log and inspected manually. (See attached
diff from RAFContainer.readPage for an example)
--
Øystein Grøvlen, Senior Staff Engineer
Sun Microsystems, Database Technology Group
Trondheim, Norway
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