Remove --with-lg-size-class-group.

Four size classes per size doubling has proven to be a universally good
choice for the entire 4.x release series, so there's little point to
preserving this configurability.

This partially resolves #580.
This commit is contained in:
Jason Evans 2017-04-21 14:49:31 -07:00
parent 120c7a747f
commit b54530020f
2 changed files with 2 additions and 39 deletions

32
INSTALL
View File

@ -220,35 +220,6 @@ any of the following arguments (not a definitive list) to 'configure':
when cross compiling, or when overriding the default for systems that do
not explicitly support huge pages.
--with-lg-size-class-group=<lg-size-class-group>
Specify the base 2 log of how many size classes to use for each doubling in
size. By default jemalloc uses <lg-size-class-group>=2, which results in
e.g. the following size classes:
[...], 64,
80, 96, 112, 128,
160, [...]
<lg-size-class-group>=3 results in e.g. the following size classes:
[...], 64,
72, 80, 88, 96, 104, 112, 120, 128,
144, [...]
The minimal <lg-size-class-group>=0 causes jemalloc to only provide size
classes that are powers of 2:
[...],
64,
128,
256,
[...]
An implementation detail currently limits the total number of small size
classes to 255, and a compilation error will result if the
<lg-size-class-group> you specify cannot be supported. The limit is
roughly <lg-size-class-group>=4, depending on page size.
--with-lg-quantum=<lg-quantum>
Specify the base 2 log of the minimum allocation alignment. jemalloc needs
to know the minimum alignment that meets the following C standard
@ -272,8 +243,7 @@ any of the following arguments (not a definitive list) to 'configure':
this allocator noncompliance means that it is generally safe in practice to
let jemalloc's minimum alignment follow glibc's lead. If you specify
--with-lg-quantum=3 during configuration, jemalloc will provide additional
size classes that are not 16-byte-aligned (24, 40, and 56, assuming
--with-lg-size-class-group=2).
size classes that are not 16-byte-aligned (24, 40, and 56).
--with-lg-tiny-min=<lg-tiny-min>
Specify the base 2 log of the minimum tiny size class to support. Tiny

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@ -1401,12 +1401,6 @@ AC_ARG_WITH([lg_page_sizes],
[Base 2 logs of system page sizes to support])],
[LG_PAGE_SIZES="$with_lg_page_sizes"], [LG_PAGE_SIZES="$LG_PAGE"])
AC_ARG_WITH([lg_size_class_group],
[AS_HELP_STRING([--with-lg-size-class-group=<lg-size-class-group>],
[Base 2 log of size classes per doubling])],
[LG_SIZE_CLASS_GROUP="$with_lg_size_class_group"],
[LG_SIZE_CLASS_GROUP="2"])
dnl ============================================================================
dnl jemalloc configuration.
dnl
@ -2022,7 +2016,7 @@ AC_CONFIG_COMMANDS([include/jemalloc/internal/public_unnamespace.h], [
])
AC_CONFIG_COMMANDS([include/jemalloc/internal/size_classes.h], [
mkdir -p "${objroot}include/jemalloc/internal"
"${SHELL}" "${srcdir}/include/jemalloc/internal/size_classes.sh" "${LG_QUANTA}" ${LG_TINY_MIN} "${LG_PAGE_SIZES}" ${LG_SIZE_CLASS_GROUP} > "${objroot}include/jemalloc/internal/size_classes.h"
"${SHELL}" "${srcdir}/include/jemalloc/internal/size_classes.sh" "${LG_QUANTA}" ${LG_TINY_MIN} "${LG_PAGE_SIZES}" 2 > "${objroot}include/jemalloc/internal/size_classes.h"
], [
SHELL="${SHELL}"
srcdir="${srcdir}"
@ -2030,7 +2024,6 @@ AC_CONFIG_COMMANDS([include/jemalloc/internal/size_classes.h], [
LG_QUANTA="${LG_QUANTA}"
LG_TINY_MIN=${LG_TINY_MIN}
LG_PAGE_SIZES="${LG_PAGE_SIZES}"
LG_SIZE_CLASS_GROUP=${LG_SIZE_CLASS_GROUP}
])
AC_CONFIG_COMMANDS([include/jemalloc/jemalloc_protos_jet.h], [
mkdir -p "${objroot}include/jemalloc"