diff options
Diffstat (limited to 'third_party/git/t/helper/test-lazy-init-name-hash.c')
| -rw-r--r-- | third_party/git/t/helper/test-lazy-init-name-hash.c | 265 |
1 files changed, 265 insertions, 0 deletions
diff --git a/third_party/git/t/helper/test-lazy-init-name-hash.c b/third_party/git/t/helper/test-lazy-init-name-hash.c new file mode 100644 index 000000000000..b99a37080d93 --- /dev/null +++ b/third_party/git/t/helper/test-lazy-init-name-hash.c @@ -0,0 +1,265 @@ +#include "test-tool.h" +#include "cache.h" +#include "parse-options.h" + +static int single; +static int multi; +static int count = 1; +static int dump; +static int perf; +static int analyze; +static int analyze_step; + +/* + * Dump the contents of the "dir" and "name" hash tables to stdout. + * If you sort the result, you can compare it with the other type + * mode and verify that both single and multi produce the same set. + */ +static void dump_run(void) +{ + struct hashmap_iter iter_dir; + struct hashmap_iter iter_cache; + + /* Stolen from name-hash.c */ + struct dir_entry { + struct hashmap_entry ent; + struct dir_entry *parent; + int nr; + unsigned int namelen; + char name[FLEX_ARRAY]; + }; + + struct dir_entry *dir; + struct cache_entry *ce; + + read_cache(); + if (single) { + test_lazy_init_name_hash(&the_index, 0); + } else { + int nr_threads_used = test_lazy_init_name_hash(&the_index, 1); + if (!nr_threads_used) + die("non-threaded code path used"); + } + + dir = hashmap_iter_first(&the_index.dir_hash, &iter_dir); + while (dir) { + printf("dir %08x %7d %s\n", dir->ent.hash, dir->nr, dir->name); + dir = hashmap_iter_next(&iter_dir); + } + + ce = hashmap_iter_first(&the_index.name_hash, &iter_cache); + while (ce) { + printf("name %08x %s\n", ce->ent.hash, ce->name); + ce = hashmap_iter_next(&iter_cache); + } + + discard_cache(); +} + +/* + * Run the single or multi threaded version "count" times and + * report on the time taken. + */ +static uint64_t time_runs(int try_threaded) +{ + uint64_t t0, t1, t2; + uint64_t sum = 0; + uint64_t avg; + int nr_threads_used; + int i; + + for (i = 0; i < count; i++) { + t0 = getnanotime(); + read_cache(); + t1 = getnanotime(); + nr_threads_used = test_lazy_init_name_hash(&the_index, try_threaded); + t2 = getnanotime(); + + sum += (t2 - t1); + + if (try_threaded && !nr_threads_used) + die("non-threaded code path used"); + + if (nr_threads_used) + printf("%f %f %d multi %d\n", + ((double)(t1 - t0))/1000000000, + ((double)(t2 - t1))/1000000000, + the_index.cache_nr, + nr_threads_used); + else + printf("%f %f %d single\n", + ((double)(t1 - t0))/1000000000, + ((double)(t2 - t1))/1000000000, + the_index.cache_nr); + fflush(stdout); + + discard_cache(); + } + + avg = sum / count; + if (count > 1) + printf("avg %f %s\n", + (double)avg/1000000000, + (try_threaded) ? "multi" : "single"); + + return avg; +} + +/* + * Try a series of runs varying the "istate->cache_nr" and + * try to find a good value for the multi-threaded criteria. + */ +static void analyze_run(void) +{ + uint64_t t1s, t1m, t2s, t2m; + int cache_nr_limit; + int nr_threads_used = 0; + int i; + int nr; + + read_cache(); + cache_nr_limit = the_index.cache_nr; + discard_cache(); + + nr = analyze; + while (1) { + uint64_t sum_single = 0; + uint64_t sum_multi = 0; + uint64_t avg_single; + uint64_t avg_multi; + + if (nr > cache_nr_limit) + nr = cache_nr_limit; + + for (i = 0; i < count; i++) { + read_cache(); + the_index.cache_nr = nr; /* cheap truncate of index */ + t1s = getnanotime(); + test_lazy_init_name_hash(&the_index, 0); + t2s = getnanotime(); + sum_single += (t2s - t1s); + the_index.cache_nr = cache_nr_limit; + discard_cache(); + + read_cache(); + the_index.cache_nr = nr; /* cheap truncate of index */ + t1m = getnanotime(); + nr_threads_used = test_lazy_init_name_hash(&the_index, 1); + t2m = getnanotime(); + sum_multi += (t2m - t1m); + the_index.cache_nr = cache_nr_limit; + discard_cache(); + + if (!nr_threads_used) + printf(" [size %8d] [single %f] non-threaded code path used\n", + nr, ((double)(t2s - t1s))/1000000000); + else + printf(" [size %8d] [single %f] %c [multi %f %d]\n", + nr, + ((double)(t2s - t1s))/1000000000, + (((t2s - t1s) < (t2m - t1m)) ? '<' : '>'), + ((double)(t2m - t1m))/1000000000, + nr_threads_used); + fflush(stdout); + } + if (count > 1) { + avg_single = sum_single / count; + avg_multi = sum_multi / count; + if (!nr_threads_used) + printf("avg [size %8d] [single %f]\n", + nr, + (double)avg_single/1000000000); + else + printf("avg [size %8d] [single %f] %c [multi %f %d]\n", + nr, + (double)avg_single/1000000000, + (avg_single < avg_multi ? '<' : '>'), + (double)avg_multi/1000000000, + nr_threads_used); + fflush(stdout); + } + + if (nr >= cache_nr_limit) + return; + nr += analyze_step; + } +} + +int cmd__lazy_init_name_hash(int argc, const char **argv) +{ + const char *usage[] = { + "test-tool lazy-init-name-hash -d (-s | -m)", + "test-tool lazy-init-name-hash -p [-c c]", + "test-tool lazy-init-name-hash -a a [--step s] [-c c]", + "test-tool lazy-init-name-hash (-s | -m) [-c c]", + "test-tool lazy-init-name-hash -s -m [-c c]", + NULL + }; + struct option options[] = { + OPT_BOOL('s', "single", &single, "run single-threaded code"), + OPT_BOOL('m', "multi", &multi, "run multi-threaded code"), + OPT_INTEGER('c', "count", &count, "number of passes"), + OPT_BOOL('d', "dump", &dump, "dump hash tables"), + OPT_BOOL('p', "perf", &perf, "compare single vs multi"), + OPT_INTEGER('a', "analyze", &analyze, "analyze different multi sizes"), + OPT_INTEGER(0, "step", &analyze_step, "analyze step factor"), + OPT_END(), + }; + const char *prefix; + uint64_t avg_single, avg_multi; + + prefix = setup_git_directory(); + + argc = parse_options(argc, argv, prefix, options, usage, 0); + + /* + * istate->dir_hash is only created when ignore_case is set. + */ + ignore_case = 1; + + if (dump) { + if (perf || analyze > 0) + die("cannot combine dump, perf, or analyze"); + if (count > 1) + die("count not valid with dump"); + if (single && multi) + die("cannot use both single and multi with dump"); + if (!single && !multi) + die("dump requires either single or multi"); + dump_run(); + return 0; + } + + if (perf) { + if (analyze > 0) + die("cannot combine dump, perf, or analyze"); + if (single || multi) + die("cannot use single or multi with perf"); + avg_single = time_runs(0); + avg_multi = time_runs(1); + if (avg_multi > avg_single) + die("multi is slower"); + return 0; + } + + if (analyze) { + if (analyze < 500) + die("analyze must be at least 500"); + if (!analyze_step) + analyze_step = analyze; + if (single || multi) + die("cannot use single or multi with analyze"); + analyze_run(); + return 0; + } + + if (!single && !multi) + die("require either -s or -m or both"); + + if (single) + time_runs(0); + if (multi) + time_runs(1); + + return 0; +} |