[Seaside] MinimalMorphic based web images

[Jimmie Houchin]

Adrian Lienhard wrote:
> On Oct 19, 2007, at 18:35 , Jimmie Houchin wrote:
>> Adrian Lienhard wrote:
[snip]
>>> Very likely it's the UI loop (GC activity depends on number of 
>>> instantiated objects, not on time elapsed). You can suspend/resume 
>>> the UI process, for example with the Seaside snapshot application, if 
>>> you want to spare some cycles (which can be significant as soon as 
>>> you have many images).
>>> Oh, and make sure that the preference named betterPerformance is 
>>> turned _off_.
>>
>> Hello Adrian,
>>
>> Thanks for the reply. From my playing around with suspending the UI it 
>> does seem to be the UI loop causing the regular (once a second or so) 
>> 2-5% spike in CPU. Suspending UI makes the Squeak process flat until 
>> serving something.
>>
>> As I am hoping to get Squeak/Seaside hosting on my web host provider, 
>> this is a very important issue.
>>
>> I am glad you made me aware of that setting. Is that the setting where 
>> Squeak decides to be more aggressive on its CPU use? I am sure a 
>> hosting provider would definitely want that turned off.
> 
> Actually, the preference is named #higherPerformance (not 
> betterPerformance). The UI loops with a default delay of 20ms. If this 
> preference is enabled, it loops with 1ms (which makes absolutely no 
> sense on a server). By default it should be turned off (in the 3.9 
> process it once was accidentally turned on, which caused me some 
> headache until I found the cause for the sudden much higher CPU use).
> 
> Cheers,
> Adrian
> 
> PS: This is also related to a problem I recently had on a production 
> application where sometimes Seaside suddenly stopped serving (see 
> http://bugs.squeak.org/view.php?id=6581). While the problem was quite 
> complex to debug, the fix I use is trivial: just increase the cycle 
> pause to 50ms...

Thanks for this information. I think it is a good thing to started 
collecting the collective wisdom from all of you who have deployed 
Seaside apps so that we can learn from you and not have to repeat any of 
the problems or headaches.

We definitely want to make repeatable positive experiences for people 
choosing Squeak and/or Seaside. And it will be nice to get some exposure 
in the web hosting provider marketplace.

Again, thanks.

Jimmie