Performance issues when upgrading from 0.38 to 0.39

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Hi all,

We've found performance drop in python-sybase when upgrading from 0.38 =
to 0.39.
We run it on Linux, python version 2.5.4 and python-sybase is linked to =
15.0.0.7 version of sybase client library.

The problem occur when we are fetching the results of a select query =
from the server. The difference between 0.38 and 0.39 is huge, we found =
0.39 is about 10-100 times slower than 0.38.

Please find the test script attached (rename it to .py). There's no =
difference in what table we select, it could contain text or number, it =
may have only one column or more columns.

Usually we get the following output when using 0.38:
Took 3.626094 seconds to fetch 10000 rows: 2757.788330 rows/second

And from 0.39:
Took 647.513509 seconds to fetch 10000 rows: 15.443693 rows/second

If I replace the line calling execute() to the following:
cursor.execute('SELECT top %d * FROM test_table' % rows, select=3DFalse)

...then in 0.39 it becomes fast, getting similar results as in 0.38.
It seems to me that using ct_cursor (which can be disabled by =
select=3DFalse) results the performance drop in 0.39.
Is there any reason to use ct_cursor or any drawback of not using it?

Is this problem general? Or does it occur in our enviroment?=20

Thank you in advance,
Zsolt

Zsolt Cserna
Morgan Stanley | IDEAS Practice Areas
Lechner Odon fasor 8 | Floor 07
Budapest, 1095
Phone: +36 1 881-3968
[email protected]

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