Mercurial > hg > blitz_condensed
annotate src/org/dancres/blitz/config/TimeBarrierPersistent.java @ 34:6f68e94c1fb8 default tip
Add CondensedStats monitoring utility, equivalent to vmstat
author | Dominic Cleal <dominic-cleal@cdo2.com> |
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date | Thu, 05 Aug 2010 11:07:25 +0100 |
parents | 3dc0c5604566 |
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Initial checkin of blitz 2.0 fcs - no installer yet.
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1 package org.dancres.blitz.config; |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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2 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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3 /** |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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4 <p>Configures Blitz to make operations durable after a certain period of |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
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5 time such that if an operation was submitted more than that time period ago, |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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6 it is guarenteed to be durable.</p> |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
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7 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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8 <p>This kind of persistence provides the developer/administrator with the |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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9 ability to trade persistence guarentee for speed. Certain applications can |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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10 tolerate this sort of behaviour because they incorporate their own |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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11 consistency checks which allow them to recover a certain amount of recent |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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12 state that the space hadn't yet persisted.</p> |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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13 */ |
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Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
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14 public class TimeBarrierPersistent extends PersistentBase { |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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15 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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16 private long theFlushTime; |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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17 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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18 /** |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
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19 @param shouldReset specifies whether to reset the ObjectOutputStream |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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20 used for logging. This is a performance vs memory tradeoff |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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21 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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22 @param shouldClean specifies whether old log files and snapshots should |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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23 be cleaned up or left for archiving. |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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24 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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25 @param aMaxLogsBeforeSync is the maximum number of log entries before |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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26 a checkpoint is forced. |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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27 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
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28 @param aLogBufferSize especially useful when doing flushing |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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29 All commands are rendered to the buffer before going to disk in one |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
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30 large block. Without the buffer, each command will trickle to disk as a |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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31 small update which isn't good for throughput! |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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32 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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33 @param aFlushTime the period in millis after which a logged command |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
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34 should be made durable. |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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35 */ |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
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36 public TimeBarrierPersistent(boolean shouldReset, boolean shouldClean, |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
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37 int aMaxLogsBeforeSync, int aLogBufferSize, |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
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38 long aFlushTime) { |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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39 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
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40 super(shouldReset, shouldClean, aLogBufferSize, aMaxLogsBeforeSync); |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
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41 theFlushTime = aFlushTime; |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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42 } |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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43 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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44 public long getFlushTime() { |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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45 return theFlushTime; |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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46 } |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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47 } |