From: Lothar Scholz Date: 2005-04-08T19:39:42+09:00 Subject: Re: Seven new VMs, all in a row Hello Lothar, LS> Hello Avi, AB>> Sorry, my last post was meant to be in reply to Lothar's request for a AB>> VM spec. I still haven't got the hang of this new google groups UI... LS> Yes, nice but this is Squeak. It seems that this is just a bytecode LS> machine without a JIT. Is there any document available vor VisualWorks ? just found this paragraph and then stopped reading the document: --------------------------- In a typical system it often turns out that the same message is sent to instances of the same class again and again; consider how often we use arrays of SmallInteger or Character or String. To improve average performance, the VM can cache the found method. If the same combination of the method and the receiver's class are found in the cache, we avoid a repeat of the full search of the MethodDictionary chain. See the method Interpreter > lookupInMethodCacheSel:class: for the implementation. VisualWorks and some other commercial Smalltalks use inline cacheing, whereby the cached target and some checking information is included inline with the dynamically translated methods. Although more efficient, it is more complex and has strong interactions with the details of the cpu instruction and data caches. --------------------------- So message dispatching with squeak is not much more efficent then what i expect from YARV, a simple bytecode dispatcher with dynamic method lookup tables and a small lookup cache. It now seems to be a simple question of the GC and there i would again vote for the Boehm Weisser GC which is a quite fast incremental GC working on all popular platforms and much easier to integrate (even with typing hints) into "gc.c" then your project. Did you ever thought about the legal problems of your problems when using the visual works engine ? I did a short look at the cincom webpage and i guess it is as expensive as ever, which means > 5000 US$ per license. I hate it when the guys are not even publishing there prices without a contact form. -- Best regards, emailto: scholz at scriptolutions dot com Lothar Scholz http://www.ruby-ide.com CTO Scriptolutions Ruby, PHP, Python IDE 's