| /////////////////////////////////////////////////////////////////////////////// |
| // |
| /// \file hardware.c |
| /// \brief Detection of available hardware resources |
| // |
| // Author: Lasse Collin |
| // |
| // This file has been put into the public domain. |
| // You can do whatever you want with this file. |
| // |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| #include "private.h" |
| |
| |
| /// Maximum number of worker threads. This can be set with |
| /// the --threads=NUM command line option. |
| static uint32_t threads_max = 1; |
| |
| /// Memory usage limit for compression |
| static uint64_t memlimit_compress; |
| |
| /// Memory usage limit for decompression |
| static uint64_t memlimit_decompress; |
| |
| /// Total amount of physical RAM |
| static uint64_t total_ram; |
| |
| |
| extern void |
| hardware_threads_set(uint32_t n) |
| { |
| if (n == 0) { |
| // Automatic number of threads was requested. |
| // If threading support was enabled at build time, |
| // use the number of available CPU cores. Otherwise |
| // use one thread since disabling threading support |
| // omits lzma_cputhreads() from liblzma. |
| #ifdef MYTHREAD_ENABLED |
| threads_max = lzma_cputhreads(); |
| if (threads_max == 0) |
| threads_max = 1; |
| #else |
| threads_max = 1; |
| #endif |
| } else { |
| threads_max = n; |
| } |
| |
| return; |
| } |
| |
| |
| extern uint32_t |
| hardware_threads_get(void) |
| { |
| return threads_max; |
| } |
| |
| |
| extern void |
| hardware_memlimit_set(uint64_t new_memlimit, |
| bool set_compress, bool set_decompress, bool is_percentage) |
| { |
| if (is_percentage) { |
| assert(new_memlimit > 0); |
| assert(new_memlimit <= 100); |
| new_memlimit = (uint32_t)new_memlimit * total_ram / 100; |
| } |
| |
| if (set_compress) { |
| memlimit_compress = new_memlimit; |
| |
| #if SIZE_MAX == UINT32_MAX |
| // FIXME? |
| // |
| // When running a 32-bit xz on a system with a lot of RAM and |
| // using a percentage-based memory limit, the result can be |
| // bigger than the 32-bit address space. Limiting the limit |
| // below SIZE_MAX for compression (not decompression) makes |
| // xz lower the compression settings (or number of threads) |
| // to a level that *might* work. In practice it has worked |
| // when using a 64-bit kernel that gives full 4 GiB address |
| // space to 32-bit programs. In other situations this might |
| // still be too high, like 32-bit kernels that may give much |
| // less than 4 GiB to a single application. |
| // |
| // So this is an ugly hack but I will keep it here while |
| // it does more good than bad. |
| // |
| // Use a value less than SIZE_MAX so that there's some room |
| // for the xz program and so on. Don't use 4000 MiB because |
| // it could look like someone mixed up base-2 and base-10. |
| #ifdef __mips__ |
| // For MIPS32, due to architectural pecularities, |
| // the limit is even lower. |
| const uint64_t limit_max = UINT64_C(2000) << 20; |
| #else |
| const uint64_t limit_max = UINT64_C(4020) << 20; |
| #endif |
| |
| // UINT64_MAX is a special case for the string "max" so |
| // that has to be handled specially. |
| if (memlimit_compress != UINT64_MAX |
| && memlimit_compress > limit_max) |
| memlimit_compress = limit_max; |
| #endif |
| } |
| |
| if (set_decompress) |
| memlimit_decompress = new_memlimit; |
| |
| return; |
| } |
| |
| |
| 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. |
| const uint64_t memlimit = mode == MODE_COMPRESS |
| ? memlimit_compress : memlimit_decompress; |
| return memlimit != 0 ? memlimit : UINT64_MAX; |
| } |
| |
| |
| /// Helper for hardware_memlimit_show() to print one human-readable info line. |
| static void |
| memlimit_show(const char *str, uint64_t value) |
| { |
| // The memory usage limit is considered to be disabled if value |
| // is 0 or UINT64_MAX. This might get a bit more complex once there |
| // is threading support. See the comment in hardware_memlimit_get(). |
| if (value == 0 || value == UINT64_MAX) |
| printf("%s %s\n", str, _("Disabled")); |
| else |
| printf("%s %s MiB (%s B)\n", str, |
| uint64_to_str(round_up_to_mib(value), 0), |
| uint64_to_str(value, 1)); |
| |
| return; |
| } |
| |
| |
| extern void |
| hardware_memlimit_show(void) |
| { |
| if (opt_robot) { |
| printf("%" PRIu64 "\t%" PRIu64 "\t%" PRIu64 "\n", total_ram, |
| memlimit_compress, memlimit_decompress); |
| } else { |
| // TRANSLATORS: Test with "xz --info-memory" to see if |
| // the alignment looks nice. |
| memlimit_show(_("Total amount of physical memory (RAM): "), |
| total_ram); |
| memlimit_show(_("Memory usage limit for compression: "), |
| memlimit_compress); |
| memlimit_show(_("Memory usage limit for decompression: "), |
| memlimit_decompress); |
| } |
| |
| tuklib_exit(E_SUCCESS, E_ERROR, message_verbosity_get() != V_SILENT); |
| } |
| |
| |
| extern void |
| hardware_init(void) |
| { |
| // Get the amount of RAM. If we cannot determine it, |
| // use the assumption defined by the configure script. |
| total_ram = lzma_physmem(); |
| if (total_ram == 0) |
| total_ram = (uint64_t)(ASSUME_RAM) * 1024 * 1024; |
| |
| // Set the defaults. |
| hardware_memlimit_set(0, true, true, false); |
| return; |
| } |