[ZODB-Dev] Using zodb and blobs

[Christian Theune]

On 04/14/2010 01:25 AM, Nitro wrote:
>>>> 40 tps sounds low:  are you pushing blob content over the wire somehow?
>>
>> I have seen the ZEO storage committing transactions at least an order of
>> magnitude faster than that (e.g., when processing incoming newswire
>> feeds). I would guess that there could have been some other latencies
>> involved in your setup (e.g., that 0-100ms lag you mention below).
>
> See my attached test script. It outputs 45-55 transactions/s for 100
> byte sized payload. Maybe there's a very fundamental flaw in the way the
> test is setup. Note that I am testing on a regular desktop machine
> (Windows 7, WoW64, 4GB RAM, 1TB hard disk capable of transfer rates
>  >100MB/s).

I don't think the transfer rate is actually that interesting. For small 
but many transactions the seek time/spinning speed should have the 
limiting influence.

I've run the attached script a couple of times on my notebook, here's 
the results:

0.11 909.090909091
0.15 666.666666667
0.2 500.0
0.07 1428.57142857
0.07 1428.57142857
0.14 714.285714286

The initial runs are a bit lower as they were interfered with by other 
applications writing to the disk.

It's a notebook w/ Intel P9600, Seagate 7.2k SATA drive, 4GB RAM, Ubuntu 
10.04, linux 2.6.32, ext4

Christian

-- 
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