Huge memory leak in expression evaluation

Huge memory leak in expression evaluation

[Andreas Schwab]

There appears to be a huge memory leak in the expression evaluator.  For
example when I set a conditional breakpoint on a frequently executed
line gdb quickly grows in the order of 500mb per second.  When I make
the breakpoint unconditional, but add commands to call continue when the
condition is not satisfied I still see some big growth, but only in the
order of 100mb per second.  The difference is probably because
breakpoint commands are executed much slower.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
PGP key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

Re: Huge memory leak in expression evaluation

[Daniel Jacobowitz]

On Fri, Jun 01, 2007 at 05:06:38PM +0200, Andreas Schwab wrote:
> There appears to be a huge memory leak in the expression evaluator.  For
> example when I set a conditional breakpoint on a frequently executed
> line gdb quickly grows in the order of 500mb per second.  When I make
> the breakpoint unconditional, but add commands to call continue when the
> condition is not satisfied I still see some big growth, but only in the
> order of 100mb per second.  The difference is probably because
> breakpoint commands are executed much slower.

Is this new, do you know?  Otherwise, valgrind works fine on GDB
nowadays; we'll have to use it.  I had gotten a base GDB session down
to no leaks at one point, though the patch was never committed because
of an ugly wart.

-- 
Daniel Jacobowitz
CodeSourcery

Re: Huge memory leak in expression evaluation

[Andreas Schwab]

Daniel Jacobowitz <drow@false.org> writes:

> Is this new, do you know?

I don't know.

> Otherwise, valgrind works fine on GDB nowadays; we'll have to use it.

Unfortunately, valgrind does not support ia64.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
PGP key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

Re: Huge memory leak in expression evaluation

[Andreas Schwab]

Daniel Jacobowitz <drow@false.org> writes:

> Is this new, do you know?

At least gdb 6.5 has the same problem.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
PGP key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

Re: Huge memory leak in expression evaluation

[Aman Wardak]

Andreas Schwab wrote:
> There appears to be a huge memory leak in the expression evaluator.  For
> example when I set a conditional breakpoint on a frequently executed
> line gdb quickly grows in the order of 500mb per second.  When I make
>   
Sorry, did you mean here 500mb or 500kb?  I'm seeing 500kb/sec growth on 
a conditional breakpoint.
Aman
> the breakpoint unconditional, but add commands to call continue when the
> condition is not satisfied I still see some big growth, but only in the
> order of 100mb per second.  The difference is probably because
> breakpoint commands are executed much slower.
>
> Andreas.
>
>   

Re: Huge memory leak in expression evaluation

[Andreas Schwab]

Aman Wardak <awardak@mvista.com> writes:

> Andreas Schwab wrote:
>> There appears to be a huge memory leak in the expression evaluator.  For
>> example when I set a conditional breakpoint on a frequently executed
>> line gdb quickly grows in the order of 500mb per second.  When I make
>>   
> Sorry, did you mean here 500mb or 500kb?

The former.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
PGP key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."