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https://issues.apache.org/jira/browse/IGNITE-11687?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16810748#comment-16810748
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Alexey Goncharuk commented on IGNITE-11687:
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I believe this was broken long ago when {{SegmentedRingByteBuffer}} was
introduced. In WAL manager we have the following code:
{code}
hdl.written += hdl.fileIO.writeFully(buf);
{code}
which appears to write a fully serialized batch of records, however, this may
be not the case when ring byte buffer returns a list of buffers to write.
At the first glance, it should be enough to update {{written}} field after all
buffers polled from the ring are written in {{WALWriter}}. [~agura], what do
you think?
> Concurrent WAL replay & log may fail with CRC error on read
> -----------------------------------------------------------
>
> Key: IGNITE-11687
> URL: https://issues.apache.org/jira/browse/IGNITE-11687
> Project: Ignite
> Issue Type: Bug
> Reporter: Alexey Goncharuk
> Priority: Major
>
> The cause is the way {{end}} is calculated for WAL iterator:
> {code}
> if (hnd != null)
> end = hnd.position();
> {code}
> {code}
> @Override public FileWALPointer position() {
> lock.lock();
> try {
> return new FileWALPointer(getSegmentId(), (int)written, 0);
> }
> finally {
> lock.unlock();
> }
> }
> {code}
> Consider a partially written entry. In this case, {{written}} has been
> already updated, concurrent WAL replay will attempt to read the incompletely
> written record and since {{end}} is not null, iterator will fail with CRC
> error.
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