Re:Intel releases the last Itanium chip, the 9700
by chrisseaton on Monday May 15, 2017 @07:19PM
(#14346070)
You've just said that you 'can't speculate about parallelism when dealing with shared resource', and then gave me an example of a system that did exactly that. Clearly, it is possible to do speculative parallelism of shared resources. We may not yet know how to make it efficient, but it is possible.
Re:Intel releases the last Itanium chip, the 9700
by thesz on Tuesday May 16, 2017 @06:10AM
(#14348509)
From what I gather, STM in .Net heavily relies on the static program analysis.
You may see it as a proof of your point, but I see it as a counterexample - a team of smart people was not able make speculative parallelism efficient even with static analysis. JIT will be even less efficient as it has to keep and account for tracing information and for speculation logs. These two interact in interesting way, I guess.
Because Microsoft tried to add STM to the .Net and get 4x slower code after extensive effort: http://www.mail-archive.com/[email protected]/msg7973...
Should I continue from these two arguments?