Mercurial > hg > blitz_stable

comparison src/org/dancres/blitz/config/TimeBarrierPersistent.java @ 0:3dc0c5604566

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Initial checkin of blitz 2.0 fcs - no installer yet.
author Dan Creswell <dan.creswell@gmail.com>
date Sat, 21 Mar 2009 11:00:06 +0000
parents
children
comparison
equal deleted inserted replaced
-1:000000000000 0:3dc0c5604566
1 package org.dancres.blitz.config;
2
3 /**
4 <p>Configures Blitz to make operations durable after a certain period of
5 time such that if an operation was submitted more than that time period ago,
6 it is guarenteed to be durable.</p>
7
8 <p>This kind of persistence provides the developer/administrator with the
9 ability to trade persistence guarentee for speed. Certain applications can
10 tolerate this sort of behaviour because they incorporate their own
11 consistency checks which allow them to recover a certain amount of recent
12 state that the space hadn't yet persisted.</p>
13 */
14 public class TimeBarrierPersistent extends PersistentBase {
15
16 private long theFlushTime;
17
18 /**
19 @param shouldReset specifies whether to reset the ObjectOutputStream
20 used for logging. This is a performance vs memory tradeoff
21
22 @param shouldClean specifies whether old log files and snapshots should
23 be cleaned up or left for archiving.
24
25 @param aMaxLogsBeforeSync is the maximum number of log entries before
26 a checkpoint is forced.
27
28 @param aLogBufferSize especially useful when doing flushing
29 All commands are rendered to the buffer before going to disk in one
30 large block. Without the buffer, each command will trickle to disk as a
31 small update which isn't good for throughput!
32
33 @param aFlushTime the period in millis after which a logged command
34 should be made durable.
35 */
36 public TimeBarrierPersistent(boolean shouldReset, boolean shouldClean,
37 int aMaxLogsBeforeSync, int aLogBufferSize,
38 long aFlushTime) {
39
40 super(shouldReset, shouldClean, aLogBufferSize, aMaxLogsBeforeSync);
41 theFlushTime = aFlushTime;
42 }
43
44 public long getFlushTime() {
45 return theFlushTime;
46 }
47 }