Re: webaxe-4 server asserts

From: Alex Rousskov (rousskov@measurement-factory.com)
Date: Mon Jun 24 2002 - 12:57:29 MDT


On Mon, 24 Jun 2002, Larry Creech wrote:

> I've been experiencing random but frequent asserts on polysrv from
> the POST entries in the req_method for the robots making it very
> difficult to get a reliable test. If I remove the POST entry from
> the req_method in the guts.pg file the asserts go away.
>
> 018.39| i-framp 12649 25.80 331 0.00 0 21
> 018.47| i-framp 12739 17.99 324 0.00 0 23
> SrvXact.cc:559: assertion failed: 'pathLen >= 0'
> Abort trap
>
> I have this problem on versions 2.7.2 through 2.7.6. Any ideas on
> how to debug this?

Hmm.. Had not seen those myself before, which is strange given that we ran
many WebAxe tests. There are two possibilities I would investigate first:

        - Polygraph cannot parse valid POST requests after they
          are modified by your HTTP intermediary; maybe some
          persistent connection or pipelining issues request body
          size?

        - the bug does not exist; your problem is related to
          faulty compiler, or hardware, or the intermediary
          is sending malformed requests to Polygraph servers

I would suggest two steps to start with:

        - use "--dump reqs" option for polysrv; this option
          may show us request headers causing the abort;
          use --console option to capture output and send it
          to me (compressed if needed)

        - replace Assert()ions in SrvXact::checkUri()
          with if-statements that emit an error message and
          return errOther; this change may let you run the
          test despite errors while we are debugging; if you
          cannot modify the function, please let me know and
          I will send you a patch OR just send me the --dump
          reqs output -- perhaps it has enough info to proceed.

Thank you,

Alex.
 



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