diff options
| author | Emilio Jesus Gallego Arias | 2020-09-16 22:20:13 +0200 |
|---|---|---|
| committer | Emilio Jesus Gallego Arias | 2020-11-16 15:44:42 +0100 |
| commit | 6a6069d55f0be157ff177150594fabcbc4b1f283 (patch) | |
| tree | da0609afecff04a95824697499a7f45f464b7510 | |
| parent | fb186f25abeb0565bb6e238345f0c5147b697322 (diff) | |
[gc] Set GC policy as best-fit in OCaml >= 4.10.0
Closes #11277 ; the `space_overhead` parameter has been selected for
maximum speedup, in some cases it could also increase memory
consumption. Please use `OCAMLRUNPARAM` to tune it and report back
your experiments.
| -rw-r--r-- | doc/changelog/07-commands-and-options/13040-gc+best_fit.rst | 9 | ||||
| -rw-r--r-- | toplevel/coqtop.ml | 17 |
2 files changed, 23 insertions, 3 deletions
diff --git a/doc/changelog/07-commands-and-options/13040-gc+best_fit.rst b/doc/changelog/07-commands-and-options/13040-gc+best_fit.rst new file mode 100644 index 0000000000..74818f8464 --- /dev/null +++ b/doc/changelog/07-commands-and-options/13040-gc+best_fit.rst @@ -0,0 +1,9 @@ +- **Changed:** + When compiled with OCaml >= 4.10.0, Coq will use the new best-fit GC + policy, which should provide some performance benefits. Coq's policy + is optimized for speed, but could increase memory consumption in + some cases. You are welcome to tune it using the ``OCAMLRUNPARAM`` + variable and report back setting so we could optimize more. + (`#13040 <https://github.com/coq/coq/pull/13040>`_, + fixes `#11277 <https://github.com/coq/coq/issues/11277>`_, + by Emilio Jesus Gallego Arias). diff --git a/toplevel/coqtop.ml b/toplevel/coqtop.ml index bbcfcc4826..d0d50aee70 100644 --- a/toplevel/coqtop.ml +++ b/toplevel/coqtop.ml @@ -149,6 +149,18 @@ let print_query opts = function heap increment and the GC pressure coefficient. *) +let set_gc_policy () = + Gc.set { (Gc.get ()) with + Gc.minor_heap_size = 32*1024*1024 (* 32Mwords x 8 bytes/word = 256Mb *) + ; Gc.space_overhead = 120 + } + +let set_gc_best_fit () = + Gc.set { (Gc.get ()) with + Gc.allocation_policy = 2 (* best-fit *) + ; Gc.space_overhead = 200 + } + let init_gc () = try (* OCAMLRUNPARAM environment variable is set. @@ -160,9 +172,8 @@ let init_gc () = (* OCAMLRUNPARAM environment variable is not set. * In this case, we put in place our preferred configuration. *) - Gc.set { (Gc.get ()) with - Gc.minor_heap_size = 32*1024*1024; (* 32Mwords x 8 bytes/word = 256Mb *) - Gc.space_overhead = 120} + set_gc_policy (); + if Coq_config.caml_version_nums >= [4;10;0] then set_gc_best_fit () else () let init_process () = (* Coq's init process, phase 1: |