Subj : Implementing Resource Control in Spider Monkey
To   : netscape.public.mozilla.jseng
From : sajidraza@hotmail.com (S. Raza)
Date : Mon Mar 08 2004 12:35 pm

I'm interested in implementing some form of resource control for
scripts that execute in my application. Specifically, CPU and memory
consumption need to be managed, on a per script basis. Ideally :) I'd
like to do this without modifying the internals of the scripting
engine. I can see that Spider Monkey supports limiting the stack-size
for a context out of the box (great). However, for heap-based objects
I don't see how this could be accomplished on a per context basis
without some changes. I guess allocating a runtime per-script with a
max runtime size begins to address the memory issue, however,
allocating a new JSRuntime object for each script request might be too
much. I'm thinking about intercepting calls to JS_NewObject. Would
that be reasonable?

Secondly for CPU usage, the js_Interpret function seems to be a nice
place to inject any CPU usage checks. Basically for let the
interpreter execute for N ops, and then check the elapsed 'real' CPU
usage for the process each time. The other possibility as in JSEAL is
to re-write byte-code to enable call-backs into CPU usage checking
code after executing some block of code.

TIA,

Raza

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