Ari,
> Very many people have stayed on the 5.0.x releases due to perceived problems with 5.1.x. There is nothing in either of those releases that should make the slightest difference to Cayenne.
I did some more research and found a report with *similar* symptoms
http://bugs.mysql.com/bug.php?id=16979
The complaint is that in an early 5.0 MySQL:
"When accessing the auto-increment counter, InnoDB uses a special table-level AUTO-INC lock that it keeps to the end of the current SQL statement, "
This appears to document anomalous locking behavior associated with MySQL 5.0 innodb, that the subsequent postings suggest will be fixed in 5.1. If this is in fact table level locking then a simple update could cause problems when there are multiple users reading & writing data. (I have no idea how to reproduce this, or test the extent to which the innodb locking has cascading affects, however if this could cause connection problems then it could be the culprit)
You guys know way more about DBMS behavior than I; does this sound like it could be the problem (remember the logs show the locking exception is typically just prior to the connection exception)?
If so, then a simple upgrade to MySQL 5.1 might fix the problem.
Thanks,
Joe
On Apr 16, 2010, at 10:51 PM, Aristedes Maniatis wrote:
> On 17/04/10 11:49 AM, Joe Baldwin wrote:
>> the database is running on a production machine:
>>
>> Sun MySQL - 5.0.51a
>> Linux 2.6.25-14.fc9.x86_64 (amd64)
>> Java 1.6
>>
>> One thing I noticed was that my webhost is using MySQL 5.0.51a, while Wikipedia documents 5.1.45 as the most recent stable release. The JDBC driver is provided by the host.
>>
>> I am not sure why they are using 5.0.51a. Could this cause a problem with Cayenne?
>
>
> Very many people have stayed on the 5.0.x releases due to perceived problems with 5.1.x. There is nothing in either of those releases that should make the slightest difference to Cayenne.
>
> You should look at running a recent version of the JDBC driver.
>
> Ari
>
>
> --
> -------------------------->
> Aristedes Maniatis
> ish
> http://www.ish.com.au
> Level 1, 30 Wilson Street Newtown 2042 Australia
> phone +61 2 9550 5001 fax +61 2 9550 4001
> GPG fingerprint CBFB 84B4 738D 4E87 5E5C 5EFA EF6A 7D2E 3E49 102A
This archive was generated by hypermail 2.0.0 : Sat Apr 17 2010 - 02:51:33 EDT