Re: Troubleshooting "too many concurrent requests"

These might help:

http://stackoverflow.com/questions/10424442/what-are-the-connection-limits-for-google-cloud-sql-from-app-engine-and-how-to

http://stackoverflow.com/questions/10158805/whats-a-good-approach-to-managing-the-db-connection-in-a-google-cloud-sql-gae/10438622#10438622

On Fri, Jun 22, 2012 at 2:48 AM, Jake Czyz <jjc.work@gmail.com> wrote:

Hello,

I've been working on a GAE / Cloud SQL app for many weeks and keep
hitting the wall on various GC-SQL limits that have forced me to
refactor my app several times.  A persistent one I'm running into is
the error:

google.storage.speckle.python.api.rdbms.0: Instance has too many
concurrent requests: 101

Does anyone have any advice for troubleshooting this error or
otherwise coding database connections in a way that
minimizes/mitigates this limitation?

My app has a couple hundred clients, and I've already had to refactor
it substantially to use the datastore instead of GC-SQL for most
interaction with clients (data is then synced to-from GC-SQL via cron
jobs... which also are exceeding the 60 second Deadline occasionally,
but that's another issue...).  Right now, there's only a single type
of request that my clients still perform that needs to access the
GC-SQL DB directly (as opposed to datastore), due to consistency
requirements. This request happens, ballpark, once every 30 seconds or
so, on average, though sometimes there are a bunch in a row (i.e. one
every couple seconds for a minute or two).

I can't even view processes (i.e. via "show processlist") and kill
threads via the Google APIs console SQL Prompt, as it displays "Failed
to load databases."   I know that restarting my instance (and waiting
several minutes) usually will get me back on track, but I've gotten
frustrated and am wondering what other strategies or ideas folks have
for dealing with the database connection limits.

Thanks in advance,
Jake