Fix large write cause tiflash crash (release-6.5)

[JaySon-Huang]

Manual cherry-pick of #7335

---

What problem does this PR solve?

Issue Number: close #7316

Problem Summary:

The root cause is BlobStore<Trait>::handleLargeWrite get a buffer from MemoryWriteBuffer and access the memory by write.size, which exceed the memory bound. MemoryWriteBuffer actually is composed by a list of chunks

tiflash/dbms/src/Storages/Page/V3/BlobStore.cpp

Lines 190 to 216 in b2b976e

	BufferBase::Buffer data_buf = write.read_buffer->buffer();
	digest.update(data_buf.begin(), write.size);
	entry.checksum = digest.checksum();
	UInt64 field_begin, field_end;
	for (size_t i = 0; i < write.offsets.size(); ++i)
	{
	ChecksumClass field_digest;
	field_begin = write.offsets[i].first;
	field_end = (i == write.offsets.size() - 1) ? write.size : write.offsets[i + 1].first;
	field_digest.update(data_buf.begin() + field_begin, field_end - field_begin);
	write.offsets[i].second = field_digest.checksum();
	}
	if (!write.offsets.empty())
	{
	// we can swap from WriteBatch instead of copying
	entry.field_offsets.swap(write.offsets);
	}
	try
	{
	auto blob_file = getBlobFile(blob_id);
	blob_file->write(data_buf.begin(), offset_in_file, write.size, write_limiter);

What is changed and how it works?

The write batch data size is large, we do NOT copy the data into a temporary buffer in order to make the memory usage of tiflash more smooth. Instead, we process the data in ReadBuffer in a streaming manner.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Fix a crash issue when tiflash persists the data of a large Region

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• Lloyd-Pottiger
• lidezhu

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[JaySon-Huang]

/run-all-tests

[JaySon-Huang]

/run-all-tests

[JaySon-Huang]

/run-all-tests

[Lloyd-Pottiger]

/run-integration-test

[JaySon-Huang]

/run-all-tests

[JaySon-Huang]

/merge

[ti-chi-bot]

@JaySon-Huang: It seems you want to merge this PR, I will help you trigger all the tests:

/run-all-tests

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[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 61cec2d

[JaySon-Huang]

/cherry-pick release-6.5-20230425-v6.5.2

[ti-chi-bot]

@JaySon-Huang: new pull request created to branch release-6.5-20230425-v6.5.2: #7377.

In response to this:

/cherry-pick release-6.5-20230425-v6.5.2

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