On Jun 22, 2009, at 11:31 AM, Alan Runyan wrote:
> On Mon, Jun 22, 2009 at 10:06 AM, Andreas Jung<li...@zopyx.com> wrote:
>> On 22.06.09 16:56, Pedro Ferreira wrote:
>>> Hello all,
>>> We occasionally get some messages like this in the logs:
>>> 2009-06-22T14:12:42 (30651/126.96.36.199:35787) Transaction
>>> waiting for storage. Clients waiting: 1.
>>> But today we eventually got to:
>>> 2009-06-22T16:00:11 (30651/188.8.131.52:53416) Transaction blocked
>>> waiting for storage. Clients waiting: 204.
>>> Which lasted some minutes. During that time, our system seemed to
>>> even if it was possible to connect to the db through the command
>>> It eventually went back to normal by itself.
>>> Any clue on what might have caused this?
>> The reason is likely a long running transaction. Since the storage
>> is single-threaded, a long running transaction will block pending
> Will the ZEO server respond to LOAD requests from ZEO clients while
> WRITEs are pending?
Yes, however, if the last phase of 2-phase commit takes long enough,
clients will become blocked altogether. This is because vote requests
get blocked and eventually, all of the client threads are blocked
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