Re: [ros-dev] Recent horrid slowdown

[WaxDragon]

(Alex's mail is down)

Phillip Susi wrote:
 
>   About a week or two ago usetup took about 20 seconds
> on my system under qemu to copy over the installation files.  I thought even that seemed a
> bit slow, so I started rewriting the code to use memory mapped files to see if I could
> speed it up.  Now that I finished with it, I noticed that the current code in the
> repository now takes just over 90 seconds to install the files, which my changes reduce
> back down to 20 seconds.
>  Does anyone have any idea about what revision this huge slowdown was introduced in? 
> I'll try and figure out the problem tonight but it would help if someone could point
> me towards the vicinity of it now so I don't have to spend time looking when I get
> home.
>
>  I'd like to get the normal code back to it's former 20 second install area so I
> can get a good comparison with my new code.  I'd be thrilled if it then could get the
> install times down to 10 seconds.
>
>  
What happened is that you either:
 
1) Enabled debugging in usetup (you didn't, didn't you? I remember on
the IRC...)
and/or
2) Reduced qemu's memory to 64MB.
 
At least both WD and I thought there was a slowdown as well.... like I
reported to you. But I noticed that it was because I had reduced the
memory. Upgrading it back to 128MB made usetup take like 10 seconds.
 
If anything, it means your patch greatly reduces memory usage and is
much more efficient. Try it with debugging off and 128MB.
 
Best regards,
Alex Ionescu