Re: Possible race condition with mod_jk + multiple workers in recovery mode

2011-01-21 Thread Andy Wang
On 01/17/2011 04:53 AM, Rainer Jung wrote: > On 13.01.2011 00:36, Andy Wang wrote: >> Aahh, having the maintenance thread do a periodic probe would be >> awesome. >> >> I see what you mean about parallel probing delaying request handling, >> but what would you think about modifying the loop so that

Re: Possible race condition with mod_jk + multiple workers in recovery mode

2011-01-17 Thread Rainer Jung
On 13.01.2011 00:36, Andy Wang wrote: Aahh, having the maintenance thread do a periodic probe would be awesome. I see what you mean about parallel probing delaying request handling, but what would you think about modifying the loop so that after going through all the JK_WORKER_USABLE() workers t

Re: Possible race condition with mod_jk + multiple workers in recovery mode

2011-01-12 Thread Andy Wang
On 01/12/2011 03:36 PM, Rainer Jung wrote: > > That was meant as an improvement. "Recovery" is only used, when a > worker has been in error state for enough time (by default 60 seconds) > and we want to find out whether it is still in error or not. mod_jk > has no active probing with test URLs, so

Re: Possible race condition with mod_jk + multiple workers in recovery mode

2011-01-12 Thread Rainer Jung
On 12.01.2011 00:59, Andy Wang wrote: I'm not sure, but it looks like the service() function in jk_lb_worker.c calls puts a recovering worker into the JK_LB_STATE_PROBE state and then doesn't set it to JK_LB_STATE_OK until after the end->service() call. I think this allows a second thread to com

Re: Possible race condition with mod_jk + multiple workers in recovery mode

2011-01-11 Thread Andy Wang
I'm not sure, but it looks like the service() function in jk_lb_worker.c calls puts a recovering worker into the JK_LB_STATE_PROBE state and then doesn't set it to JK_LB_STATE_OK until after the end->service() call. I think this allows a second thread to come in, and since JK_WORKER_USABLE() retur

Possible race condition with mod_jk + multiple workers in recovery mode

2011-01-11 Thread Andy Wang
I'm still digging, but I thought I'd send this along to the mailing list while I try to decipher the mod_jk code. We're using tomcat-connector 1.2.31 on apache 2.2.17 on a Linux system. Log file is at this URL: http://www.moonteeth.com/~dopey/tomcat/mod_jk.log