Legend

0
uninitialized
X
no feedback
1
monomorphic
^
recompute handler
P
polymorphic
N
megamorphic
G
generic

Instructions

Unified web interface to analyse runtime information stored in the v8 log.

For generating a v8.log file from d8:
  • /path/do/d8 $LOG_FLAGS $FILE
For generating a v8.log file from Chrome:
  • /path/to/chrome --user-data-dir=/var/tmp/chr$RANDOM --no-sandbox --js-flags='$LOG_FLAGS’ $WEBSITE_URL

LOG_FLAGS:

--log-all
Enable all V8 logging options.
--log-maps
Log Maps
--log-ic
Log ICs
--log-source-code
Log source code
--log-code-disassemble
Log detailed generated generated code
--log-code
Log details about deoptimized code
--log-deopt
Log various API uses.
--prof
Log ticks from the sampling profiler.

Local Symbol Server

To get detailed C++ symbols for local binaries you can host the system-analyzer locally using tools/system-analyzer/local-server.sh. You can then access the analyzer on localhost.

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