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Diffstat (limited to 'examples/java/com/wiredtiger/examples/ex_stat.java')
| -rw-r--r-- | examples/java/com/wiredtiger/examples/ex_stat.java | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/examples/java/com/wiredtiger/examples/ex_stat.java b/examples/java/com/wiredtiger/examples/ex_stat.java new file mode 100644 index 00000000000..c81bb64c22a --- /dev/null +++ b/examples/java/com/wiredtiger/examples/ex_stat.java @@ -0,0 +1,252 @@ +/*- + * 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.java + * This is an example demonstrating how to query database statistics. + */ +package com.wiredtiger.examples; +import com.wiredtiger.db.*; +import java.io.*; +import java.util.*; + +public class ex_stat { + + public static String home; + + /*! [statistics display function] */ + int + print_cursor(Cursor cursor) + throws WiredTigerException + { + String desc, pvalue; + long value; + int ret; + + while ((ret = cursor.next()) == 0) { + desc = cursor.getValueString(); + pvalue = cursor.getValueString(); + value = cursor.getValueLong(); + if (value != 0) + System.out.println(desc + "=" + pvalue); + } + + return (ret == wiredtiger.WT_NOTFOUND ? 0 : ret); + } + /*! [statistics display function] */ + + int + print_database_stats(Session session) + throws WiredTigerException + { + Cursor cursor; + int ret; + + /*! [statistics database function] */ + cursor = session.open_cursor("statistics:", null, null); + + ret = print_cursor(cursor); + ret = cursor.close(); + /*! [statistics database function] */ + + return (ret); + } + + int + print_file_stats(Session session) + throws WiredTigerException + { + Cursor cursor; + int ret; + + /*! [statistics table function] */ + cursor = session.open_cursor("statistics:table:access", null, null); + ret = print_cursor(cursor); + ret = cursor.close(); + /*! [statistics table function] */ + + return (ret); + } + + int + print_overflow_pages(Session session) + throws WiredTigerException + { + /*! [statistics retrieve by key] */ + Cursor cursor; + String desc, pvalue; + long value; + int ret; + + cursor = session.open_cursor("statistics:table:access", null, null); + + cursor.putKeyInt(wiredtiger.WT_STAT_DSRC_BTREE_OVERFLOW); + ret = cursor.search(); + desc = cursor.getValueString(); + pvalue = cursor.getValueString(); + value = cursor.getValueLong(); + System.out.println(desc + "=" + pvalue); + + ret = cursor.close(); + /*! [statistics retrieve by key] */ + + return (ret); + } + + /*! [statistics calculation helper function] */ + long + get_stat(Cursor cursor, int stat_field) + throws WiredTigerException + { + long value; + int ret; + + cursor.putKeyInt(stat_field); + if ((ret = cursor.search()) != 0) { + System.err.println("stat_field: " + stat_field + " not found"); + value = 0; + } + else { + String desc = cursor.getValueString(); + String pvalue = cursor.getValueString(); + value = cursor.getValueLong(); + } + return (value); + } + /*! [statistics calculation helper function] */ + + int + print_derived_stats(Session session) + throws WiredTigerException + { + Cursor cursor; + int ret; + + /*! [statistics calculate open table stats] */ + cursor = session.open_cursor("statistics:table:access", null, null); + /*! [statistics calculate open table stats] */ + + { + /*! [statistics calculate table fragmentation] */ + long ckpt_size = get_stat(cursor, + wiredtiger.WT_STAT_DSRC_BLOCK_CHECKPOINT_SIZE); + long file_size = get_stat(cursor, + wiredtiger.WT_STAT_DSRC_BLOCK_SIZE); + + System.out.println("File is " + + (int)(100 * (file_size - ckpt_size) / file_size) + + "% fragmented\n"); + /*! [statistics calculate table fragmentation] */ + } + + { + /*! [statistics calculate write amplification] */ + long app_insert = get_stat(cursor, + wiredtiger.WT_STAT_DSRC_CURSOR_INSERT_BYTES); + long app_remove = get_stat(cursor, + wiredtiger.WT_STAT_DSRC_CURSOR_REMOVE_BYTES); + long app_update = get_stat(cursor, + wiredtiger.WT_STAT_DSRC_CURSOR_UPDATE_BYTES); + + long fs_writes = get_stat(cursor, + wiredtiger.WT_STAT_DSRC_CACHE_BYTES_WRITE); + + if (app_insert + app_remove + app_update != 0) + System.out.println("Write amplification is " + + (double)fs_writes / (app_insert + app_remove + app_update)); + /*! [statistics calculate write amplification] */ + } + + ret = cursor.close(); + + return (ret); + } + + public int + statExample() + throws WiredTigerException + { + Connection conn; + Cursor cursor; + 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 (System.getenv("WIREDTIGER_HOME") == null) { + home = "WT_HOME"; + try { + Process proc = Runtime.getRuntime().exec("/bin/rm -rf WT_HOME"); + BufferedReader br = new BufferedReader( + new InputStreamReader(proc.getInputStream())); + while(br.ready()) + System.out.println(br.readLine()); + br.close(); + new File("WT_HOME").mkdir(); + } catch (IOException ioe) { + System.err.println("IOException: WT_HOME: " + ioe); + return(1); + } + } else + home = null; + + conn = wiredtiger.open(home, "create,statistics=(all)"); + session = conn.open_session(null); + + ret = session.create("table:access", "key_format=S,value_format=S"); + + cursor = session.open_cursor("table:access", null, null); + cursor.putKeyString("key"); + cursor.putValueString("value"); + ret = cursor.insert(); + ret = cursor.close(); + + ret = session.checkpoint(null); + + ret = print_database_stats(session); + + ret = print_file_stats(session); + + ret = print_overflow_pages(session); + + ret = print_derived_stats(session); + + return (conn.close(null) == 0 ? ret : -1); + } + + public static int + main(String[] argv) + { + try { + return ((new ex_stat()).statExample()); + } + catch (WiredTigerException wte) { + System.err.println("Exception: " + wte); + return (-1); + } + } +} |