From 29fd321033276261b87da7be5223db33d879a4c7 Mon Sep 17 00:00:00 2001 From: Lasse Collin Date: Fri, 2 Oct 2009 14:35:56 +0300 Subject: [PATCH] Add support for --enable-assume-ram=SIZE. --- INSTALL | 16 ++++++++++++++++ configure.ac | 24 ++++++++++++++++++++++++ src/xz/hardware.c | 7 +++---- src/xzdec/xzdec.c | 5 +++-- 4 files changed, 46 insertions(+), 6 deletions(-) diff --git a/INSTALL b/INSTALL index f6bc4502..48ba0ff4 100644 --- a/INSTALL +++ b/INSTALL @@ -237,6 +237,22 @@ XZ Utils Installation to optimize for size. You need to add -Os or equivalent flag(s) to CFLAGS manually. + --enable-assume-ram=SIZE + On the most common operating systems, XZ Utils is able to + detect the amount of physical memory on the system. This + information is used to set the default memory usage limit. + + On some systems, there is no code to detect the amount of + RAM though. Using --enable-assume-ram one can set how much + memory to assume on these systems. SIZE is given as MiB. + The default is 32 MiB, which is probably too low for most + systems, but it is enough to allow decompressing .xz files + created with the default settings. + + Feel free to send patches to add support for detecting + the amount of RAM on the operating system you use. See + src/common/tuklib_physmem.c for details. + --disable-threads Disable threading support. This makes some things thread-unsafe, meaning that if multithreaded application diff --git a/configure.ac b/configure.ac index c576d224..d4a51ffd 100644 --- a/configure.ac +++ b/configure.ac @@ -380,6 +380,30 @@ AC_MSG_RESULT([$enable_threads]) # We use the actual result a little later. +######################### +# Assumed amount of RAM # +######################### + +# We use 32 MiB as default, because it should be small enough for most +# cases and allows decompressing files compressed with the default settings. +# Probably it is too small for most systems, but it's safer to guess too low. +AC_MSG_CHECKING([how much RAM to assume if the real amount is unknown]) +AC_ARG_ENABLE([assume-ram], AC_HELP_STRING([--enable-assume-ram=SIZE], + [If and only if the real amount of RAM cannot be determined, + assume SIZE MiB. The default is 32 MiB. This affects the + default memory usage limit.]), + [], [enable_assume_ram=32]) +assume_ram_check=`echo "$enable_assume_ram" | tr -d 0123456789` +if test -z "$enable_assume_ram" || test -n "$assume_ram_check"; then + AC_MSG_RESULT([]) + AC_MSG_ERROR([--enable-assume-ram accepts only an integer argument]) +fi +AC_MSG_RESULT([$enable_assume_ram MiB]) +AC_DEFINE_UNQUOTED([ASSUME_RAM], [$enable_assume_ram], + [How many MiB of RAM to assume if the real amount cannot + be determined.]) + + ############################################ # xz/xzdec/lzmadec linkage against liblzma # ############################################ diff --git a/src/xz/hardware.c b/src/xz/hardware.c index cb094abd..d5f4b9b4 100644 --- a/src/xz/hardware.c +++ b/src/xz/hardware.c @@ -68,11 +68,10 @@ hardware_memlimit_set_percentage(uint32_t percentage) uint64_t mem = tuklib_physmem(); - // If we cannot determine the amount of RAM, assume 32 MiB. Maybe - // even that is too much on some systems. But on most systems it's - // far too little, and can be annoying. + // If we cannot determine the amount of RAM, use the assumption + // defined by the configure script. if (mem == 0) - mem = UINT64_C(32) * 1024 * 1024; + mem = (uint64_t)(ASSUME_RAM) * 1024 * 1024; memlimit = percentage * mem / 100; return; diff --git a/src/xzdec/xzdec.c b/src/xzdec/xzdec.c index 18bdb04e..4f40f1d6 100644 --- a/src/xzdec/xzdec.c +++ b/src/xzdec/xzdec.c @@ -106,9 +106,10 @@ memlimit_set_percentage(uint32_t percentage) { uint64_t mem = tuklib_physmem(); - // If we cannot determine the amount of RAM, assume 32 MiB. + // If we cannot determine the amount of RAM, use the assumption + // set by the configure script. if (mem == 0) - mem = UINT64_C(32) * 1024 * 1024; + mem = (uint64_t)(ASSUME_RAM) * 1024 * 1024; memlimit = percentage * mem / 100; return;