Re: [webkit-dev] Making WTF::StringImpl and WTF::AtomString thread-safe

2020-12-09 Thread Darin Adler via webkit-dev
> On Dec 9, 2020, at 1:02 PM, Geoff Garen via webkit-dev > wrote: > >> - Make FontCache thread-safe, but do it via introducing a completely >> separate thread-safe AtomString type and leave the current one as it is >> (I don't have a good grasp of how difficult this would actually be) > > I

Re: [webkit-dev] Making WTF::StringImpl and WTF::AtomString thread-safe

2020-12-09 Thread Geoff Garen via webkit-dev
>> 1. It’s not just ref counting. >> >> To make String thread-safe, you also need to address all other data >> members. That means all state in m_hashAndFlags, including the >> 8bit/16bit state. >> >> It appears that your testing strategy did not reveal this point so >> far; so, you probably

Re: [webkit-dev] Making WTF::StringImpl and WTF::AtomString thread-safe

2020-12-09 Thread Geoff Garen via webkit-dev
>> Because it’s so expensive, and because we have a no regression policy for >> performance, I don’t think there’s a way to land this change in pieces. It >> has to be a mega-patch, so we can test its performance as a whole. > > Were you able to quantify anything additional about the

Re: [webkit-dev] Making WTF::StringImpl and WTF::AtomString thread-safe

2020-12-02 Thread Sam Weinig via webkit-dev
Hey Geoff and Chris, > On Dec 1, 2020, at 9:21 AM, Geoff Garen via webkit-dev > wrote: > > A few thoughts here: > > 1. It’s not just ref counting. > > To make String thread-safe, you also need to address all other data members. > That means all state in m_hashAndFlags, including the

Re: [webkit-dev] Making WTF::StringImpl and WTF::AtomString thread-safe

2020-12-02 Thread Chris Lord via webkit-dev
On 2020-12-01 18:21, Geoff Garen wrote: > A few thoughts here: > > 1. It’s not just ref counting. > > To make String thread-safe, you also need to address all other data > members. That means all state in m_hashAndFlags, including the > 8bit/16bit state. > > It appears that your testing

Re: [webkit-dev] Making WTF::StringImpl and WTF::AtomString thread-safe

2020-12-01 Thread Geoff Garen via webkit-dev
A few thoughts here: 1. It’s not just ref counting. To make String thread-safe, you also need to address all other data members. That means all state in m_hashAndFlags, including the 8bit/16bit state. It appears that your testing strategy did not reveal this point so far; so, you probably