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Diffstat (limited to 'src/third_party/wiredtiger/examples/c/ex_stat.c')
| -rw-r--r-- | src/third_party/wiredtiger/examples/c/ex_stat.c | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/src/third_party/wiredtiger/examples/c/ex_stat.c b/src/third_party/wiredtiger/examples/c/ex_stat.c new file mode 100644 index 00000000000..65402230eb8 --- /dev/null +++ b/src/third_party/wiredtiger/examples/c/ex_stat.c @@ -0,0 +1,227 @@ +/*- + * Public Domain 2014-2016 MongoDB, Inc. + * Public Domain 2008-2014 WiredTiger, Inc. + * + * This is free and unencumbered software released into the public domain. + * + * Anyone is free to copy, modify, publish, use, compile, sell, or + * distribute this software, either in source code form or as a compiled + * binary, for any purpose, commercial or non-commercial, and by any + * means. + * + * In jurisdictions that recognize copyright laws, the author or authors + * of this software dedicate any and all copyright interest in the + * software to the public domain. We make this dedication for the benefit + * of the public at large and to the detriment of our heirs and + * successors. We intend this dedication to be an overt act of + * relinquishment in perpetuity of all present and future rights to this + * software under copyright law. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. + * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + * + * ex_stat.c + * This is an example demonstrating how to query database statistics. + */ + +#include <inttypes.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include <wiredtiger.h> + +int print_cursor(WT_CURSOR *); +int print_database_stats(WT_SESSION *); +int print_file_stats(WT_SESSION *); +int print_overflow_pages(WT_SESSION *); +int get_stat(WT_CURSOR *cursor, int stat_field, uint64_t *valuep); +int print_derived_stats(WT_SESSION *); + +static const char *home; + +/*! [statistics display function] */ +int +print_cursor(WT_CURSOR *cursor) +{ + const char *desc, *pvalue; + uint64_t value; + int ret; + + while ((ret = cursor->next(cursor)) == 0 && + (ret = cursor->get_value(cursor, &desc, &pvalue, &value)) == 0) + if (value != 0) + printf("%s=%s\n", desc, pvalue); + + return (ret == WT_NOTFOUND ? 0 : ret); +} +/*! [statistics display function] */ + +int +print_database_stats(WT_SESSION *session) +{ + WT_CURSOR *cursor; + int ret; + + /*! [statistics database function] */ + if ((ret = session->open_cursor(session, + "statistics:", NULL, NULL, &cursor)) != 0) + return (ret); + + ret = print_cursor(cursor); + ret = cursor->close(cursor); + /*! [statistics database function] */ + + return (ret); +} + +int +print_file_stats(WT_SESSION *session) +{ + WT_CURSOR *cursor; + int ret; + + /*! [statistics table function] */ + if ((ret = session->open_cursor(session, + "statistics:table:access", NULL, NULL, &cursor)) != 0) + return (ret); + + ret = print_cursor(cursor); + ret = cursor->close(cursor); + /*! [statistics table function] */ + + return (ret); +} + +int +print_overflow_pages(WT_SESSION *session) +{ + /*! [statistics retrieve by key] */ + WT_CURSOR *cursor; + const char *desc, *pvalue; + uint64_t value; + int ret; + + if ((ret = session->open_cursor(session, + "statistics:table:access", NULL, NULL, &cursor)) != 0) + return (ret); + + cursor->set_key(cursor, WT_STAT_DSRC_BTREE_OVERFLOW); + ret = cursor->search(cursor); + ret = cursor->get_value(cursor, &desc, &pvalue, &value); + printf("%s=%s\n", desc, pvalue); + + ret = cursor->close(cursor); + /*! [statistics retrieve by key] */ + + return (ret); +} + +/*! [statistics calculation helper function] */ +int +get_stat(WT_CURSOR *cursor, int stat_field, uint64_t *valuep) +{ + const char *desc, *pvalue; + int ret; + + cursor->set_key(cursor, stat_field); + if ((ret = cursor->search(cursor)) != 0) + return (ret); + + return (cursor->get_value(cursor, &desc, &pvalue, valuep)); +} +/*! [statistics calculation helper function] */ + +int +print_derived_stats(WT_SESSION *session) +{ + WT_CURSOR *cursor; + int ret; + + /*! [statistics calculate open table stats] */ + if ((ret = session->open_cursor(session, + "statistics:table:access", NULL, NULL, &cursor)) != 0) + return (ret); + /*! [statistics calculate open table stats] */ + + { + /*! [statistics calculate table fragmentation] */ + uint64_t ckpt_size, file_size, percent; + ret = get_stat(cursor, WT_STAT_DSRC_BLOCK_CHECKPOINT_SIZE, &ckpt_size); + ret = get_stat(cursor, WT_STAT_DSRC_BLOCK_SIZE, &file_size); + + percent = 0; + if (file_size != 0) + percent = 100 * ((file_size - ckpt_size) / file_size); + printf("Table is %" PRIu64 "%% fragmented\n", percent); + /*! [statistics calculate table fragmentation] */ + } + + { + /*! [statistics calculate write amplification] */ + uint64_t app_insert, app_remove, app_update, fs_writes; + + ret = get_stat(cursor, WT_STAT_DSRC_CURSOR_INSERT_BYTES, &app_insert); + ret = get_stat(cursor, WT_STAT_DSRC_CURSOR_REMOVE_BYTES, &app_remove); + ret = get_stat(cursor, WT_STAT_DSRC_CURSOR_UPDATE_BYTES, &app_update); + + ret = get_stat(cursor, WT_STAT_DSRC_CACHE_BYTES_WRITE, &fs_writes); + + if (app_insert + app_remove + app_update != 0) + printf("Write amplification is %.2lf\n", + (double)fs_writes / (app_insert + app_remove + app_update)); + /*! [statistics calculate write amplification] */ + } + + ret = cursor->close(cursor); + + return (ret); +} + +int +main(void) +{ + WT_CONNECTION *conn; + WT_CURSOR *cursor; + WT_SESSION *session; + int ret; + + /* + * Create a clean test directory for this run of the test program if the + * environment variable isn't already set (as is done by make check). + */ + if (getenv("WIREDTIGER_HOME") == NULL) { + home = "WT_HOME"; + ret = system("rm -rf WT_HOME && mkdir WT_HOME"); + } else + home = NULL; + + ret = wiredtiger_open(home, NULL, "create,statistics=(all)", &conn); + ret = conn->open_session(conn, NULL, NULL, &session); + ret = session->create( + session, "table:access", "key_format=S,value_format=S"); + + ret = session->open_cursor( + session, "table:access", NULL, NULL, &cursor); + cursor->set_key(cursor, "key"); + cursor->set_value(cursor, "value"); + ret = cursor->insert(cursor); + ret = cursor->close(cursor); + + ret = session->checkpoint(session, NULL); + + ret = print_database_stats(session); + + ret = print_file_stats(session); + + ret = print_overflow_pages(session); + + ret = print_derived_stats(session); + + return (conn->close(conn, NULL) == 0 ? ret : EXIT_FAILURE); +} |