On Saturday 07 December 2013 06:32 AM, Michael Bayer wrote:
[...]
OK more or less that, please review my commit at
https://github.com/zzzeek/sqlalchemy/commit/d1cc78479d988bd9acbcf395483d2130b0873b1c
which moves handling of “overflow” into _inc_overflow() and
_dec_overflow() methods - the
Hello,
I have faced a problem in my production server (gevent based); when a
connection attempt is made and MySQL server does not respond (due to listen
backlog full), the whole application hangs. This seems to be because
SQLAlchemy QueuePool does not allow multiple connection attempts
On Dec 6, 2013, at 10:16 AM, Sunil Adapa su...@innopark.in wrote:
Hello,
I have faced a problem in my production server (gevent based); when a
connection attempt is made and MySQL server does not respond (due to listen
backlog full), the whole application hangs. This seems to be because
On Dec 6, 2013, at 11:15 AM, Michael Bayer mike...@zzzcomputing.com wrote:
Since the overflow lock seems to be to only maintain overflow count, I
suggest that we increment the counter *before* connection attempt, don't
hold the lock during connection attempt and then decrement the counter
yeah, sorry I get this entirely now, ticket is
http://www.sqlalchemy.org/trac/ticket/2880 and here’s a test, has nothing to do
with gevent. the patch should be fine and I’ll see if i can get it into 0.8.4
as well.
from sqlalchemy.pool import QueuePool
from sqlalchemy.testing.mock import Mock,
On Dec 6, 2013, at 6:01 PM, Claudio Freire klaussfre...@gmail.com wrote:
On Fri, Dec 6, 2013 at 3:50 PM, Michael Bayer mike...@zzzcomputing.com
wrote:
+except:
+self._overflow -= 1
+raise
That also needs to aquire the lock.
I think I’m
On Dec 6, 2013, at 6:27 PM, Michael Bayer mike...@zzzcomputing.com wrote:
On Dec 6, 2013, at 6:01 PM, Claudio Freire klaussfre...@gmail.com wrote:
On Fri, Dec 6, 2013 at 3:50 PM, Michael Bayer mike...@zzzcomputing.com
wrote:
+except:
+self._overflow -= 1
+
On Friday 06 December 2013 09:45 PM, Michael Bayer wrote:
[...]
OK, I see this is with gevent - while I like the idea of gevent, I’m
not deeply familiar with best practices for it. The QueuePool
specifically uses thread-based locks to achieve it’s work. I can’t
comment on what modifications
On Saturday 07 December 2013 12:20 AM, Michael Bayer wrote:
[...]
the hard part is producing a test case. I noticed just now that
even if I take overflow_lock out entirely, all the current tests
pass, but this is because it’s not easy for tests to catch race
conditions like that. To test the
