Davisp python-spidermonkey → Version 0.1.0

Comments and changes to this ticket

• 

  Paul J. Davis May 11th, 2009 @ 12:56 AM

  (from [e203f17e196b811162a66a6446180513c0691ea5]) API for limiting resource usage.

  You can now enforce crude resource usage limits for scripts executing in the JS VM. Its not overly granular and has some caveats, but it appears to work.

  To limit the time a script can run:

  >>> rt = spidermonkey.Runtime()
  >>> cx = rt.new_context()
  >>> cx.max_time(5) # Specified in seconds, returns the previous value.
  0
  >>> cx.execute("while(true) {}")
  ...
  RuntimeError
  
  

  To limit the amount of memory is similar:

  >>> rt = spidermonkey.Runtime()
  >>> cx = rt.new_context()
  >>> cx.max_memory(10000) # Specified in bytes, returns the previous value.
  0
  >>> cx.execute("var f = []; var b = 100000; while(b-- > 0) f.push(b*0.9)")
  ...
  RuntimeError
  
  

  At the moment this looks like its limiting resources per context when in reality its per runtime. So if you limit to usage on a context, and some other script in the context is running above that limit, the limited context will fail.

  You can also get the current values without setting:

  >>> cx.max_time(10)
  ...
  >>> cx.max_time()
  10
  >>> cx.max_memory(10000)
  ...
  >>> cx.max_memory()
  10000
  
  

  Some minor tweaks to make the memory limit specified on the Runtime and to improve the reported errors to follow shortly.

  [#12] http://github.com/davisp/python-...

• 

  Paul J. Davis May 11th, 2009 @ 01:10 AM

  • State changed from “new” to “resolved”

  (from [28d3cd5ec06a60b8a4824eaa46ac13e41d7108a4]) Change exception types for resource exhaustion.

  Out of memory is now signaled by a MemoryError Too much CPU time is reported as a SystemError

  I'm going to punt on the issue with specifying memory usage limits on contexts when it really refernces the runtime. I don't see a good way to implement it without quite a bit of work. It'll never be specifiable per context, only the api might change to avoid confusion.

  [#12 state:resolved] http://github.com/davisp/python-...

• 

  Paul J. Davis May 11th, 2009 @ 09:11 PM

  (from [584ba6f0e3e7078d4a0eeed0c4094a31703a643a]) Updates to the build system.

  Linking against the library works, but importing spidermonkey kills the Python VM because of an unresolved symbol. Can't figure out if this is just OS X's build of libmozjs or if I'm missing a flag.

  [#12] http://github.com/davisp/python-...

• 

  Paul J. Davis May 11th, 2009 @ 09:21 PM

  (from [c29ad86edfb992056dbc4b9f1c10f909149abe04]) Updated the README. Thanks Mark Lee.

  [#12] http://github.com/davisp/python-...

• 

  Paul J. Davis May 31st, 2009 @ 06:31 AM

  • Milestone set to “Version 0.1.0”
  • Tag set to “resourcelimits”
  • State changed from “resolved” to “open”

  When 1.8.1 comes out the memory limit code will be even more ineffective than it already is. I just had the thought that instead of relying on spidermonkey's API to report memory, I could dip back into python for memory reporting some how.