Jexplore

jexplore - is a bundle of python scripts which help to unveil the state of underlying structures in jemalloc 4.0.4 allocator.

Install

• Add macrolist.c to the list of jemalloc src files ln -s jexplore/macrolist.c jemalloc/src/macrolist.c
• Add macrolist.h to the list of jemalloc headers ln -s jexplore/macrolist.h include/jemalloc/internal/macrolist.h
• Change include/jemalloc/internal/jemalloc_internal.h by adding #include "jemalloc/internal/macrolist.h" before #undef JEMALLOC_H_EXTERNS
• Change jemalloc Makefile variable C_SRCS += $(srcroot)src/macrolist.c
• Rebuild jemalloc
• Add source /PATH/TO/jexplore/jexplore.py to your .gdbinit file. Or type it directly in a new gdb session
• By default scripts work with python3, for python2.6 support switch to python26 upstream branch

Documentation

Read the complete documention in documentation.py file.

Basic commands are:

• je_help - print help from documentation.py
• je_init - define jemalloc macroses if they were not resolved when starting gdb session
• je_threads - print thread specific data
• je_ptr ptr - check internal jemalloc structures associated with this pointer
• je_chunk ptr - check the chunk associated with this pointer (huge)
• je_run ptr - check the run associated with this pointer (large)
• je_region ptr - check the region associated with this pointer (small)
• je_scan_sections step - detect heap sections in mmap of the process
• je_dump_chunks beg end file - dump chunks to the file from the section identified by beg and end addr.
• je_search /size-char max-count string - search string in detected heap sections (flags like gdb find)