On some builds we only get 'SmokeDMD' references during testing rather than a full file path. This adds 'SmokeDMD' to the acceptable frame description list.
On some builds we only get 'SmokeDMD' references during testing rather than a full file path. This adds 'SmokeDMD' to the acceptable frame description list.
On some builds we only get 'SmokeDMD' references during testing rather than a full file path. This adds 'SmokeDMD' to the acceptable frame description list.
On some builds we only get 'SmokeDMD' references during testing rather than a full file path. This adds 'SmokeDMD' to the acceptable frame description list.
This adds an '--allocation-filter' param that can be used to limit output to
only allocations that include the filter in their stack. For example:
dmd.py --allocation-filter fontconfig dmd.json.gz
limits its output to just allocations that have an instance of 'fontconfig' in
in one of their stack frames.
They are both infallible wrappers of posix_memalign and valloc.
There is also moz_xmemalign, which wraps memalign, which is mostly
always available as of bug 1402647.
None of them are actually used, but it's still desirable to at least
have one infallible variant, so keep moz_xmemalign and remove the other
two.
While here, we actually make both memalign and moz_xmemalign always
available.
They are both infallible wrappers of posix_memalign and valloc.
There is also moz_xmemalign, which wraps memalign, which is always
available as of bug 1402647.
None of them are actually used, but it's still desirable to at least
have one infallible variant, so keep moz_xmemalign and remove the other
two.
While here, we actually make moz_xmemalign always available, since
memalign is always available.
The current default is 24, which is equal to the maximum number of stack frames
that DMD will record. And that's a terrible value because it splits up too many
related stack traces into separate records. There is no single best value, but
8 is a much better default.
DMD currently uses a very hacky form of "sampling" by default to avoid
recording stack traces for all blocks. This makes DMD run faster than when it
records all stack traces.
This patch changes the sampling method used; in fact, it avoids "sampling" at
all. The existence of all heap blocks is now recorded exactly, but by default
we only record an allocation stack for each heap block if a Bernoulli trial
succeeds. This choice works well because getting the stack trace is ~100x
slower than recording the block's existence.
Overall, this approach is simpler and it also gives better output -- the choice
of which blocks to record allocation stacks for is mathematically sound, no
stack trace gets blamed for allocations it didn't do, and block counts and
sizes are now always exact.
Other specific things changed.
- All notion of sampling is removed from the various data structures.
- The --sample-below option is removed in favour of --stacks={partial,full}.
- The format of the JSON output file has changed.
- The names of various test files have changed to reflect concept changes.
This adds a new option --clamp-contents to dmd.py. This replaces every value
contained in the memory contents in the log with a pointer to the start of a live
block, if the value is a pointer into the middle of that block. All other values
are replaced with 0. This conservative analysis makes it easier to determine
which blocks point to other blocks.
This implements a new "scan" mode for DMD that records the address
and contents of every live unsampled block in the DMD log. This
enables the low-level analysis of references from one block to
another, which can help leak investigations.
They are kept around for the sake of the standalone glue, which is used
for e.g. webapprt, which doesn't have direct access to jemalloc, and thus
still needs a wrapper to go through the xpcom function list and get to
jemalloc from there.
The new "num" property lets identical blocks be aggregated in the output. This
patch only uses the "num" property for dead blocks, because that's where the
greatest potential benefit lies, but it could be used for live blocks as well.
On one test case (a complex PDF file) running with --mode=cumulative
--sample-below=1 this patch had the following effects.
- Change in running speed was negligible.
- Compressed output file size dropped from 8.8 to 5.0 MB.
- Compressed output file size dropped from 297 to 50 MB.
- dmd.py runtime (without stack fixing) dropped from 30 to 8 seconds.
Now that defining $DMD is no longer necessary to run DMD, this patch does the
following.
- Removes all the places where we set DMD=1 (test harnesses, etc.)
- Still handles DMD=1, for backwards compatibility.
- Prints "$DMD is undefined" at DMD start-up if appropriate.
- Writes a |null| value for |dmdEnvVar| in the JSON if $DMD is undefined. Bumps
the DMD output version number accordingly.
- Changes a bunch of the test files accordingly, including changing the mode of
script-ignore-alloc-fns.json in order to test a case where $DMD is undefined.
This patch moves profiling mode selection from post-processing (in dmd.py) to
DMD start-up. This will make it easier to add new kinds of profiling, such as
cumulative heap profiling.
Specifically:
- There's a new --mode option. |LiveWithReports| is the default, as it is
currently.
- dmd.py's --ignore-reports option is gone.
- There's a new |mode| field in the JSON output.
- Reports-related operations are now no-ops if DMD isn't in LiveWithReports
mode.
- Diffs are only allowed for output files that have the same mode.
- A new function ResetEverything() replaces the SetSampleBelowSize() and
ClearBlocks(), which were used by the test to change DMD options.
- The tests in SmokeDMD.cpp are split up so they can be run multiple times, in
different modes. The exact combinations of tests and modes has been changed a
bit.
