Terr: What I have noticed with ANTLRWorks. The first version I started with didn't seem to have the performance and stability problems. My current version 1.3.1 does have them. I think I went through two semi-automatic upgrades (Two notifications that upgrades were available which I naturally accepted.) This version checks for ANTLR syntax errors with every keystroke, which I don't recall for my first version. So I would definitely check out recent changes.
The slowdown takes a while to appear. I think I have it more often when I am working with the string template generator files than with my large toy grammar, but I have definitely seen it with both. FWIW my suspicion is a memory leak, but there are other possibilities. I believe there was talk a few months ago of using Java's unbuffered IO as the default for ANTLR itself, which can have serious performance problems, but I suspect is not the cause here. Java's poor default hash function could also be a contributor, but that suspicion could just be because I am reading Valloud's text, and he has strong opinions on that topic. On Feb 1, 2010, at 12:40 PM, Terence Parr wrote: > Hi, > > Jean and I are re-factoring ANTLRWorks to be much simpler in anticipation of > me taking over maintenance and adding features. The first thing I want to do > is find out why AW sometimes slows to a crawl. I can't seem to reproduce it > when I want to, although it was really really slow the other day before I > decided to debug it! ;) > > So, I need your help to figure out when it occurs so that it will give me a > clue about where to look in the source code. My impression is that one of > the triggers seems to be when there are lots of errors. But, when I added a > whole bunch of grammar windows and then started randomly inserting errors all > over the grammar, memory usage didn't really go up and it didn't slow down at > all (lots other errors to the console, but that's it). I wonder though if it > was getting more memory available to it in the debugger than when I run it > from the jar file. Also, I note that sometimes undo is extremely slow, so > that is also a potential area to look. > > My current candidates for slowdown: > > * running out of memory and thrashing > * undo mechanism is tracking too much or something > * error mechanism somehow tracks too much or has too much work to do > > Each keystroke triggers colorizing the editor window, but Jean tells me he's > sure that the parser itself is okay. might be the error handling though. > > Can anybody reproduce a case where you start ANTLRWorks and then do some > stuff in the editor window with a grammar (of any size) and it starts to get > really slow to type? Even if you can't send me your grammar, I can send you > an instrumented version of AW that will turn out some information about what > is going on. > > Thanks! This is my highest priority for AW since I'm using it to build v4 > ANTLR. > > Thanks, > Ter > > List: http://www.antlr.org/mailman/listinfo/antlr-interest > Unsubscribe: > http://www.antlr.org/mailman/options/antlr-interest/your-email-address > List: http://www.antlr.org/mailman/listinfo/antlr-interest Unsubscribe: http://www.antlr.org/mailman/options/antlr-interest/your-email-address -- You received this message because you are subscribed to the Google Groups "il-antlr-interest" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/il-antlr-interest?hl=en.
