diff options
Diffstat (limited to 'src/xz/hardware.c')
| -rw-r--r-- | src/xz/hardware.c | 38 |
1 files changed, 29 insertions, 9 deletions
diff --git a/src/xz/hardware.c b/src/xz/hardware.c index 18eee7ec..2cc3f4f2 100644 --- a/src/xz/hardware.c +++ b/src/xz/hardware.c @@ -29,6 +29,13 @@ static uint64_t memlimit_decompress = 0; /// Default memory usage for multithreaded modes: /// +/// - Default value for --memlimit-compress when automatic number of threads +/// is used. However, if the limit wouldn't allow even one thread then +/// the limit is ignored in coder.c and one thread will be used anyway. +/// This mess is a compromise: we wish to prevent -T0 from using too +/// many threads but we also don't want xz to give an error due to +/// a memlimit that the user didn't explicitly set. +/// /// - Default value for --memlimit-mt-decompress /// /// This value is caluclated in hardware_init() and cannot be changed later. @@ -151,15 +158,12 @@ hardware_memlimit_set(uint64_t new_memlimit, extern uint64_t hardware_memlimit_get(enum operation_mode mode) { - // Zero is a special value that indicates the default. Currently - // the default simply disables the limit. Once there is threading - // support, this might be a little more complex, because there will - // probably be a special case where a user asks for "optimal" number - // of threads instead of a specific number (this might even become - // the default mode). Each thread may use a significant amount of - // memory. When there are no memory usage limits set, we need some - // default soft limit for calculating the "optimal" number of - // threads. + // 0 is a special value that indicates the default. + // It disables the limit in single-threaded mode. + // + // NOTE: For multithreaded decompression, this is the hard limit + // (memlimit_stop). hardware_memlimit_mtdec_get() gives the + // soft limit (memlimit_threaded). const uint64_t memlimit = mode == MODE_COMPRESS ? memlimit_compress : memlimit_decompress; return memlimit != 0 ? memlimit : UINT64_MAX; @@ -167,6 +171,22 @@ hardware_memlimit_get(enum operation_mode mode) extern uint64_t +hardware_memlimit_mtenc_get(void) +{ + return memlimit_compress == 0 && threads_are_automatic + ? memlimit_mt_default + : hardware_memlimit_get(MODE_COMPRESS); +} + + +extern bool +hardware_memlimit_mtenc_is_default(void) +{ + return memlimit_compress == 0 && threads_are_automatic; +} + + +extern uint64_t hardware_memlimit_mtdec_get(void) { uint64_t m = memlimit_mtdec != 0 |