Re: large memory allocations / resource consumption in crashtests?
On Mon, 27 Jul 2015 21:35:20 +1200, Karl Tomlinson wrote: Sometimes it would be nice to check in crashtests that use, or attempt to use large memory allocations, but I'm concerned that checking in these crashtests could disrupt subsequent tests because there is then not enough memory to test what they want to test. Following up here, mainly just to report back on findings, for anyone considering the same in the future. I ended up backing out the test that I wanted to add [1] and I think the main blocker is that at least some platforms overcommit memory. Large allocations can succeed, but the lack of memory is not detected until the memory is actually used. When the memory is used, a process is killed, and AFAIK there is no guarantee that it is the process using the new memory. Even if we configured platforms to not overcommit, I'd still be uncomfortable adding a test that may force everything to swap to disk. It seems that fallible memory allocation is only a complete solution when constrained by address space, but perhaps we could run our tests with process data segment size constraints tuned for the hardware environment. The dummy unload event listener is helpful to avoid keeping things alive in BF cache, but AFAIK SimpleTest.forceGC/CC() (or similar DOMWindowUtils methods) and carefully removing all references is the only way to ensure that memory is released immediately. [1] https://bugzilla.mozilla.org/show_bug.cgi?id=999376#c12 ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
Re: large memory allocations / resource consumption in crashtests?
On 07/27/2015 04:07 PM, Ehsan Akhgari wrote: On 2015-07-27 5:35 AM, Karl Tomlinson wrote: Is anything done between crashtests to clean up memory use? There isn't, AFAIK. Or can CC be triggered to run during or after a particular crashtest? You can use SimpleTest.forceGC/CC() as needed. Do crashtests go into B/F cache on completion, or can we know that nsGlobalWindow::CleanUp() or FreeInnerObjects() will run on completion? I'm pretty sure that pages are put into the bf cache if possible as usual. And you can test that by using pagehide event listener and check .persisted property. If you explicitly want to prevent bfcache for certain page, just add a dummy unload event listener. ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
Re: large memory allocations / resource consumption in crashtests?
Thanks everyone. That gives me some ideas on how to clean up after the page. I figure that then any OOM issues will at least be in the vicinity of the test doing the large allocation. ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
large memory allocations / resource consumption in crashtests?
Sometimes it would be nice to check in crashtests that use, or attempt to use large memory allocations, but I'm concerned that checking in these crashtests could disrupt subsequent tests because there is then not enough memory to test what they want to test. Is anything done between crashtests to clean up memory use? Or can CC be triggered to run during or after a particular crashtest? Do crashtests go into B/F cache on completion, or can we know that nsGlobalWindow::CleanUp() or FreeInnerObjects() will run on completion? ___ dev-platform mailing list dev-platform@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-platform
