Mercurial > hg > blitz_condensed
annotate src/org/dancres/blitz/txn/UnsyncdOps.java @ 0:3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
author | Dan Creswell <dan.creswell@gmail.com> |
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date | Sat, 21 Mar 2009 11:00:06 +0000 |
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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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changeset
|
2 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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3 import org.dancres.blitz.BootInfo; |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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changeset
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4 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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5 /** |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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6 <p>UnsyncdOps provides boot-time information concerning the maximum number |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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7 of log operations which might have occurred since the last full |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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8 checkpoint/sync was initiated.</p> |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
|
9 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
|
10 <p>We deliberately return double the op count to allow for interrupted |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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11 checkpoints. An interrupted checkpoint leads to two contiguous |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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12 log files with no separating checkpoint image. The maximum number |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
|
13 of operations before the next checkpoint would, therefore be |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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14 double the maximum number of ops per checkpoint. A checkpoint can |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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15 only be interrupted as the result of violent shutdown and, restart |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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16 will immediately resolve state using the UnsyncdOps. If restart |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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17 fails to complete, there will be no further log entries or |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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18 checkpoints and the next restart will, worst case, apply the |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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19 state resolution twice which isn't harmful.</p> |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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20 */ |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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21 public class UnsyncdOps implements BootInfo, java.io.Serializable { |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
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22 private int theOpCount; |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
|
23 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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24 UnsyncdOps(int anOpCount) { |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
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25 theOpCount = 2 * anOpCount; |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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26 } |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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27 |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
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28 public int getOpsSinceLastCheckpoint() { |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
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29 return theOpCount; |
3dc0c5604566
Initial checkin of blitz 2.0 fcs - no installer yet.
Dan Creswell <dan.creswell@gmail.com>
parents:
diff
changeset
|
30 } |
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 } |