[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Attachment: HBASE-16643_8.patch
One more addition to patch. Added a closed flag in case MemstoreScanner is
closed for the second time.
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch, HBASE-16643_4.patch,
> HBASE-16643_5.patch, HBASE-16643_6.patch, HBASE-16643_7.patch,
> HBASE-16643_8.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Status: Open (was: Patch Available)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch, HBASE-16643_4.patch,
> HBASE-16643_5.patch, HBASE-16643_6.patch, HBASE-16643_7.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Status: Patch Available (was: Open)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch, HBASE-16643_4.patch,
> HBASE-16643_5.patch, HBASE-16643_6.patch, HBASE-16643_7.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Attachment: HBASE-16643_7.patch
Updated patch addresses the comments. And now close() will close the scanners
individually if heap is null.
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch, HBASE-16643_4.patch,
> HBASE-16643_5.patch, HBASE-16643_6.patch, HBASE-16643_7.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Status: Open (was: Patch Available)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch, HBASE-16643_4.patch,
> HBASE-16643_5.patch, HBASE-16643_6.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Attachment: HBASE-16643_6.patch
Updated patch correcting the test case failures. Every where we are now
supposed to do the seek before we do next() call. The hbase core does it that
way only but test cases were not doing it. So we may have to update such test
cases now.
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch, HBASE-16643_4.patch,
> HBASE-16643_5.patch, HBASE-16643_6.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Status: Patch Available (was: Open)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch, HBASE-16643_4.patch,
> HBASE-16643_5.patch, HBASE-16643_6.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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回复：[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
String msg = "Results sent from server=" + noOfResults + ". But
only got " + i+ " results completely at client. Resetting the
scanner to scan again."; LOG.error(msg); throw new
DoNotRetryIOException(msg);} } catch (IOException ioe) {
// We are getting IOE while retrieving the cells for Results.
// We have to scan for the same results again. Throwing DNRIOE as a client
retry on the// same scanner will result in
OutOfOrderScannerNextExceptionLOG.error("Exception while reading
cells from result." + "Resetting the scanner to scan again.",
ioe);throw new DoNotRetryIOException("Resetting the scanner.",
ioe); } cells.add(cellScanner.current());
System.out.println("ResponseConverter.getResults(1)--cells == "+ cells + "--j
== " + j + "---noOfCells == " + noOfCells);}results[i] =
Result.create(cells, null, response.getStale(), isPartial);
System.out.println("ResponseConverter.getResults(2)--cells == "+ cells +
"--results[i] == " + results[i] + "---noOfCells == " + noOfCells); } else
{// Result is pure pb.results[i] =
ProtobufUtil.toResult(response.getResults(i));
System.out.println("ResponseConverter.getResults(3)--results == " + results[i]
+ "--i == " + i); }}return results; thank you very much, anoop, do
you want to see this code, the exception should occur on the red mark line.
- 原始邮件 -
发件人："ramkrishna.s.vasudevan (JIRA)"
收件人：issues@hbase.apache.org
主题：[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow
MSLAB closure due to improper ref counting of segments
日期：2016年09月23日 13点25分
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Status: Open (was: Patch Available)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch, HBASE-16643_4.patch,
> HBASE-16643_5.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
--
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Status: Open (was: Patch Available)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch, HBASE-16643_4.patch,
> HBASE-16643_5.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
--
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Hadoop Flags: Reviewed
Status: Patch Available (was: Open)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch, HBASE-16643_4.patch,
> HBASE-16643_5.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Attachment: HBASE-16643_5.patch
Updated patch based on RB comments. I have left some replies in the RB for all
the comments and questions. The SegmentScanner change is needed is what I
believe. If that is not needed in this JIRA I can remove it and raise another
JIRA for discussion.
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch, HBASE-16643_4.patch,
> HBASE-16643_5.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Status: Open (was: Patch Available)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch, HBASE-16643_4.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Attachment: HBASE-16643_4.patch
Updated RB with this version.
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch, HBASE-16643_4.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Status: Patch Available (was: Open)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Attachment: HBASE-16643_3.patch
Now we will initialize the heap in memstore scanner lazily depending on what
type of scanner API is called on it for the first time.
Removes synchronized from all the methods as it was mentioned in the earlier
review comment.
The patch becomes smaller because no test cases were changed and no interface
is updated though I would like to update the Store#getScanners() API and unify
them. Not sure how to do that if we cannot break without deprecating. So I have
deferred it to another JIRA.
Still I prefer changing the Store interface as it is much cleaner and passing
the reverse scan info to the getScanners() API in some form is useful and
cleaner. Will submit for QA.
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch, HBASE-16643_3.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Status: Open (was: Patch Available)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Status: Patch Available (was: Open)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Attachment: HBASE-16643_2.patch
REmoves the assertion change. It was my bad. Locally no problem as assertion
was not enabled so could not spot it.
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch,
> HBASE-16643_2.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Status: Open (was: Patch Available)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Status: Patch Available (was: Open)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Attachment: HBASE-16643_1.patch
Updated patch. The failed test case seems to pass. Will check once again with
QA.
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch, HBASE-16643_1.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Status: Open (was: Patch Available)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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[jira] [Updated] (HBASE-16643) Reverse scanner heap creation may not allow MSLAB closure due to improper ref counting of segments
[
https://issues.apache.org/jira/browse/HBASE-16643?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
ramkrishna.s.vasudevan updated HBASE-16643:
---
Summary: Reverse scanner heap creation may not allow MSLAB closure due to
improper ref counting of segments (was: Reverse scanner heap creation may not
allow MSLAB closure due to inproper ref counting of segments)
> Reverse scanner heap creation may not allow MSLAB closure due to improper ref
> counting of segments
> --
>
> Key: HBASE-16643
> URL: https://issues.apache.org/jira/browse/HBASE-16643
> Project: HBase
> Issue Type: Bug
>Reporter: ramkrishna.s.vasudevan
>Assignee: ramkrishna.s.vasudevan
>Priority: Critical
> Fix For: 2.0.0
>
> Attachments: HBASE-16643.patch
>
>
> In the reverse scanner case,
> While doing 'initBackwardHeapIfNeeded' in MemstoreScanner for setting the
> backward heap, we do a
> {code}
> if ((backwardHeap == null) && (forwardHeap != null)) {
> forwardHeap.close();
> forwardHeap = null;
> // before building the heap seek for the relevant key on the scanners,
> // for the heap to be built from the scanners correctly
> for (KeyValueScanner scan : scanners) {
> if (toLast) {
> res |= scan.seekToLastRow();
> } else {
> res |= scan.backwardSeek(cell);
> }
> }
> {code}
> forwardHeap.close(). This would internally decrement the MSLAB ref counter
> for the current active segment and snapshot segment.
> When the scan is actually closed again we do close() and that will again
> decrement the count. Here chances are there that the count would go negative
> and hence the actual MSLAB closure that checks for refCount==0 will fail.
> Apart from this, when the refCount becomes 0 after the firstClose if any
> other thread requests to close the segment, then we will end up in corrupted
> segment because the segment could be put back to the MSLAB pool.
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