Mailing List Archive

Rama K. McIntosh wrote:

> Hello Backhand Users and Developers,
>
> Due to a nasty bug/typo in backhand 1.2.1,
> Backhand byBusyChildren does not work at all.
>
> This bug was fixed in CVS about 3 months ago.
> However, I have wasted many hours trying to get backhand
> to balance properly because this bug fix was never released or a patch
> published.

The ChangeLog is marked as having that fix in 1.2.1. Upon
investigation, I see that 1.11 of builtins.h was not tagged into the
1.2.1 release. I do agree with you that this is a very deceiving bug
and should be rolled into a release. The reason it had not is because
we though it had :-)

>
> Should I be using the CVS version instead of the patched version of
> 1.2.1 I am using now?
> (i.e. are there other nasty bugs that have
> been fixed in CVS that should concern backhand users?)

Yeah. There is one particularly nasty bug that only I have seem to have
hit. It has to do with an infinite loop. After running mod_backhand on
several largish sites for years, I just hit is about 2 months ago and it
is fixed in CVS.

>
> Developers: please consider releasing a bug
> fix release. I believe this bug alone warrants
> a published patch or new version which would
> have saved me and my employer much time and money.

If you are concerned about the time and money spent trying to get a
FREE, OPEN-SOURCE product with no WARANTEE or even suitability for a
particular purpose (as the licese reads), you might consider buying
support. There are a few companies that provide consulting/support for
mod_backhand and Apache in general.

Also, a posting to the list saying that byBusyChildren was acting
inappropriately would have likely resulted in a relatively quick
solution to your problem.

> Also, please consider adding to my desired release
> byBusyChildren support to addPrediction
> ("serverstats[servers[0].id].aservers-=1;").

Sounds like a good idea.

> I do think Backhand is a great product so thanks and
> keep up the good work.


--
Theo Schlossnagle
Principal Consultant
OmniTI Computer Consulting, Inc. -- http://www.omniti.com/
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Theo Schlossnagle wrote:
...

>
> If you are concerned about the time and money spent trying to get a
> FREE, OPEN-SOURCE product with no WARANTEE or even suitability for a
> particular purpose (as the licese reads), you might consider buying
> support. There are a few companies that provide consulting/support for
> mod_backhand and Apache in general.

Thanks for everything and I agree with you 100%. I should have
conveyed that my comments of lost time and productivity where directed
towards my client and their management that where blind cc'd on my post
to the list.

>
>
> Also, a posting to the list saying that byBusyChildren was acting
> inappropriately would have likely resulted in a relatively quick
> solution to your problem. ...

This has been an ongoing thread on the list. Feedback from the list
ultmately led me to find a solution. The thread has been about my
inability make backhand balance my client's extreamly heavy applicaton
server. This was a direct symptom of the byBusyChildren bug.

Anyway, I am happy to report that I now have backhand perfectly
balancing a very heavy application server accross 5 machines under
simulated maximum load conditions. This was accomplished with the fixed
byBusyChildren and a custom addPrediction. I stress tested this farm
under very high load using Apache jmeter to simulate application use and
backhand now works perfectly.

Thanks again,
-Rama