[SOUP] Network Cache: Give more priority to reads over writes in IO WorkQueue

• Component: WebKit2
• Status: RESOLVED FIXED

[Carlos Garcia Campos]

We could keep the default priority for reads and use idle priority for writes.

[Carlos Garcia Campos]

Created attachment 254555 [details]
Patch

[WebKit Commit Bot]

Attachment 254555 [details] did not pass style-queue:


ERROR: Source/WebKit2/NetworkProcess/cache/NetworkCacheIOChannelSoup.cpp:72:  Extra space before ( in function call  [whitespace/parens] [4]
Total errors found: 1 in 2 files


If any of these errors are false positives, please file a bug against check-webkit-style.

[Sergio Villar Senin]

Comment on attachment 254555 [details]
Patch

Seems like a good idea, hope it doesn't lead to starvation

[Carlos Garcia Campos]

(In reply to comment #3)
> Comment on attachment 254555 [details]
> Patch
> 
> Seems like a good idea, hope it doesn't lead to starvation

Thanks. Well, this main loop only runs disk cache read/write tasks, so at some point it will finish reading resources from cache and writes will happen, I guess.

[Zan Dobersek]

Comment on attachment 254555 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=254555&action=review

> Source/WebKit2/NetworkProcess/cache/NetworkCacheIOChannelSoup.cpp:268
>      runTaskInQueue([channel, offset, data, completionHandler] {
>          channel->write(offset, data, completionHandler);
> -    }, queue);
> +    }, queue, G_PRIORITY_DEFAULT_IDLE);

This is never called with a non-null WorkQueue, meaning it's always scheduled on the main context. The point being, is the WorkQueue priority scheduling necessary?

[Carlos Garcia Campos]

(In reply to comment #5)
> Comment on attachment 254555 [details]
> Patch
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=254555&action=review
> 
> > Source/WebKit2/NetworkProcess/cache/NetworkCacheIOChannelSoup.cpp:268
> >      runTaskInQueue([channel, offset, data, completionHandler] {
> >          channel->write(offset, data, completionHandler);
> > -    }, queue);
> > +    }, queue, G_PRIORITY_DEFAULT_IDLE);
> 
> This is never called with a non-null WorkQueue, meaning it's always
> scheduled on the main context. The point being, is the WorkQueue priority
> scheduling necessary?

It's rather the opposite, since it always receives a work queue, it's never scheduled in the main context, but in the work queue main context, and we still want IOChannel::read() to happen before IOChannel::write().

[Carlos Garcia Campos]

Committed r185366: <http://trac.webkit.org/changeset/185366>