On Fri, 23 Aug 2019, Marcel Taeumel wrote:

> Hmm... HierarchyBrowser has a cache in #classList. Browser has no such cache. Browser >> #hierarchicalClassList is slow.
> Also, class compilation is so slow because of SmalltalkImage >> #logChange:.

I'm not sure that's true. It seems to be more like a mismeasurement by the
profiler. The following takes ~200ms on my machine (it should remove the
spam from the changes file, but use at your own risk):

| startPosition |
startPosition := (SourceFiles at: 2) size.
[ 10000 timesRepeat: [ Smalltalk logChange: 'test' ] ] timeProfile.
(SourceFiles at: 2) truncate: startPosition.

Also, #forceChangesToDisk's trick to force write-to-disk by closing and
reopening the file won't work in modern OSes. They'll realize that you're
reopening a file already in your process's cache, and will just provide
you with the cached file without forcing the contents to be written to
disk.
We have #sync to actually force write-to-disk, but using that in
#forceChangesToDisk will make the above snippet 250x slower (or more if
your storage device is not that fast).