We're seeing quite a few spins below IconDatabase::retainIconForPageURL(), we should avoid blocking the main thread on this operation (and its release sibling.)
Created attachment 142104 [details]
Here's one way we can do this- batch up the retain/release operations and execute them on the sync thread.
Comment on attachment 142104 [details]
View in context: https://bugs.webkit.org/attachment.cgi?id=142104&action=review
> + // NOTE: The caller is assumed to hold m_urlAndIconLock.
In the past I thought we had a way to ASSERT this.
Do we still?
Committed r117501: <http://trac.webkit.org/changeset/117501>