Re: -stack-list-locals and children

Niko Sams
2009-06-29T09:30:31Z

On Mon, Jun 29, 2009 at 10:17, Vladimir Prus<vladimir@codesourcery.com> wrote:
> [I assume you did not CC list accidentally, readding it back]
>
> On Monday 29 June 2009 you wrote:
>
>> >> Basic tests showed me that -var-create is relatively slow for large lists.
>> >
>> > How slow and how did you measure this? I would not expect variable objects to
>> > be considerably slower than printing the value in any other way.
>> I measured using -enable-timings. I did -var-create for a QStringList
>> with 1000 items,
>> took 0.6sec.
>
> This is the current problem with GDB -- it will always try to fetch all
> children, which has other problems besides performance. In particular,
> if you try to get children of an invalid object, gdb might never finish.
> Tom is planning to address this issue soon, and we'll be able to have
> incremental fetch of varobj children -- much like we have for stack
> frames in KDevelop already.
ok, I see.
When this is fixed -var-create should be faster?

> Also, is -stack-list-locals any better here? I'd expect it to either have
> exactly the same performance problems, or ignore pretty-printing. If it
> is considerably faster while still reporting 1000 children, it's performance
> bug somewhere.
It's much faster. I get about 100 children in the value followed by ....

Niko