Ralloc - Recoverable Lock-free Allocator

Ralloc is a persistent lock-free allocator designed for nonvolatile memory. It is introduced in Understanding and Optimizing Persistent Memory Allocation by Wentao Cai, Haosen Wen, H. Alan Beadle, Chris Kjellqvist, Mohammad Hedayati, and Michael L. Scott. The full paper is to appear in ISMM' 20. You can also find the brief announcement version of the paper in PPoPP' 20.

Warning

Current implementation doesn't support filter functions in pure C code!

Layout

• src: Ralloc's Source files.
• ext: External library.
  • makalu_alloc: the Makalu source code from Atlas repo on GitHub.
  • lrmalloc: the LRMalloc source code from lrmalloc repo on GitHub, with some minor bug fix and retweak. WARNING: Due to the small counter used in LRMalloc to avoid ABA problem, it has been encountered that a hazard counter overflow will happen and cause segfaults when #thread is big (e.g., >72). Please be aware of this if you want to run benchmarks with LRMalloc.
• test: testing code and Makefile.
  • ./: running scripts and Makefile; executables of benchmarks; libralloc.a
  • benchmark: macros and benchmarks source code.
• data:
  • genfigs.R: plotting script.
  • Others: Generated csv files by testing scripts.
• obj: Generated build artifacts (.o) organized by test/Makefile

Dependencies

Necessary

gcc with C++11 support

libjemalloc

Optional

PMDK if you want to run benchmarks with it

Usage

All following commands assume that you are in the root directory of this repo.

By default, Ralloc creates files in NVM mounted at /mnt/pmem/. If you want to instead emulate using DRAM, i.e., create files in /dev/shm/, please define macro SHM_SIMULATING while building. More details can be found in the macros Section below.

Use Ralloc in your projects

To use ralloc in other projects :

$ cd test

$ make libralloc.a

And then

1. add #include "ralloc.hpp" to files that use Ralloc's functions.
2. append -I<path_to_ralloc>/src to your compile command.
3. link libralloc.a to your project by appending -L<path_to_ralloc>/test -lralloc.a to your link command.

Benchmarks

To compile libralloc.a and all benchmarks :

$ cd test

$ make ALLOC=<r|mak|je|lr|pmdk>

By default ALLOC is r.

To compile specific target :

$ cd test

$ make <libralloc.a|threadtest_test|sh6bench_test|larson_test|prod-con_test> ALLOC=<r|mak|je|lr|pmdk>

Execution

To run all benchmarks with all allocators, do :

$ cd test

$ ./run_all.sh

The results will be written in csv files stored in ./data.

To run a specific benchmark with a particular allocator, do :

$ cd test

$ ./run_<larson|prod-con|shbench|threadtest>.sh <r|mak|je|lr|pmdk>

The results will be written in csv files stored in ./data/$0/$0_$1.csv. ($0 can be larson, prod-con, shbench, or threadtest; $1 can be r, mak, je, lr, or pmdk.)

Draw plots

We used R for drawing plots, and a sample plotting script locates in:

data/genfigs.R

Running:

$ cd data

$ Rscript ./genfigs.R

Will plot out the data located in:

data/

License

This project is licensed under the MIT license. You may find a copy of the license in the LICENSE file included in the Ralloc source distribution.

Macros

DESTROY

This macro enables the option to destroy all mapping files during the exit. This might be useful for benchmarking.

SHM_SIMULATING

This macro switches Ralloc to compatible mode for machines with no real persistent memory. In this mode, ramdisk located in /dev/shm will be used.

When this macro is not defined, allocations go to /mnt/pmem by default. If your mounting point of the persistent memory is different, please replace /mnt/pmem/ with yours in src/pm_config.hpp.

Test with different allocator

This is controlled by the following macros, but we recommend the user may to select different allocators by passing corresponding ALLOC to make. test/Makefile will handle ALLOC and define the corresponding macro to enable the target allocator, as we mentioned in the previous Benchmarks section.

RALLOC

Run with Ralloc, a lock-free persistent allocator by University of Rochester.

MAKALU

Run with Makalu, a lock-based persistent allocator by HP Lab.

PMDK

Run with libpmemobj from PMDK, a persistent memory programming toolkit by Intel.

otherwise

Directly call malloc and free. jemalloc is used by default