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annotate src/org/dancres/blitz/txn/CheckpointTrigger.java @ 35:6f68e94c1fb8 default tip

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Add CondensedStats monitoring utility, equivalent to vmstat
author Dominic Cleal <dominic-cleal@cdo2.com>
date Thu, 05 Aug 2010 11:07:25 +0100
parents 3dc0c5604566
children
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3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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1 package org.dancres.blitz.txn;
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 import org.dancres.blitz.ActiveObject;
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4
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
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5 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet.
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6 <p>Checkpoints can be triggered as the result of a number of different
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet.
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7 stimuli. Typically, these stimuli are the number of operations since the
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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8 last checkpoint or the time since the last checkpoint.</p>
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
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10 <p>Instances of this class encapsulate a particular policy with respect to
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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11 when a checkpoint should be triggered. When they determine that a
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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12 checkpoint is required, they invoke the <code>sync</code> of a
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
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13 <code>Checkpointer</code> instance (typically passed in at construction
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet.
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14 time). This call should be made in an independent thread - i.e. it is
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet.
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15 <em>not</em> appropriate for CheckpointTrigger methods to block.</p>
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Dan Creswell <dan.creswell@gmail.com>
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16
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17 @see org.dancres.blitz.txn.Checkpointer
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18 */
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19 public interface CheckpointTrigger extends ActiveObject {
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20 public void loggedCommand();
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21
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet.
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22 /**
3dc0c5604566 Initial checkin of blitz 2.0 fcs - no installer yet.
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23 @return <code>true</code> if checkpointing is not allowed.
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24 */
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25 public boolean checkpointsDisabled();
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26 }