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This commit is contained in:
Mike Kot 2021-01-12 21:46:03 +03:00
parent 6022311a37
commit 6b949109f1
2 changed files with 17 additions and 12 deletions
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22
src/Storages/StorageReplicatedMergeTree.cpp
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@ -1352,29 +1352,25 @@ bool StorageReplicatedMergeTree::executeLogEntry(LogEntry & entry)
}
bool do_fetch = false;
if (entry.type == LogEntry::GET_PART)
{
/// Before fetching the part, we need to look for it in the detached/ folder by checksum.
/// If we are lucky, we do not copy the part over the network.
// TODO
do_fetch = true;
}
else if (entry.type == LogEntry::MERGE_PARTS)
{
/// Sometimes it's better to fetch merged part instead of merge
/// For example when we don't have all source parts for merge
do_fetch = !tryExecuteMerge(entry);
}
else if (entry.type == LogEntry::MUTATE_PART)
{
/// Sometimes it's better to fetch mutated part instead of merge
do_fetch = !tryExecutePartMutation(entry);
}
else if (entry.type == LogEntry::ALTER_METADATA)
{
return executeMetadataAlter(entry);
}
else
{
throw Exception("Unexpected log entry type: " + toString(static_cast<int>(entry.type)), ErrorCodes::LOGICAL_ERROR);
}
if (do_fetch)
return executeFetch(entry);
@ -4460,13 +4456,19 @@ PartitionCommandsResultInfo StorageReplicatedMergeTree::attachPartition(
PartsTemporaryRename renamed_parts(*this, "detached/");
MutableDataPartsVector loaded_parts = tryLoadPartsToAttach(partition, attach_part, query_context, renamed_parts);
ReplicatedMergeTreeBlockOutputStream output(*this, metadata_snapshot, 0, 0, 0, false, false, false); /// TODO Allow to use quorum here.
/// TODO Allow to use quorum here.
ReplicatedMergeTreeBlockOutputStream output(*this, metadata_snapshot, 0, 0, 0, false, false, false);
for (size_t i = 0; i < loaded_parts.size(); ++i)
{
String old_name = loaded_parts[i]->name;
const String old_name = loaded_parts[i]->name;
output.writeExistingPart(loaded_parts[i]);
renamed_parts.old_and_new_names[i].first.clear();
LOG_DEBUG(log, "Attached part {} as {}", old_name, loaded_parts[i]->name);
results.push_back(PartitionCommandResultInfo{
.partition_id = loaded_parts[i]->info.partition_id,
.part_name = loaded_parts[i]->name,

7
src/Storages/StorageReplicatedMergeTree.h
View File

@ -39,13 +39,14 @@ namespace DB
* - the structure of the table (/metadata, /columns)
* - action log with data (/log/log-...,/replicas/replica_name/queue/queue-...);
* - a replica list (/replicas), and replica activity tag (/replicas/replica_name/is_active), replica addresses (/replicas/replica_name/host);
* - select the leader replica (/leader_election) - these are the replicas that assigning merges, mutations and partition manipulations
* - the leader replica election (/leader_election) - these are the replicas that assign merges, mutations
* and partition manipulations.
* (after ClickHouse version 20.5 we allow multiple leaders to act concurrently);
* - a set of parts of data on each replica (/replicas/replica_name/parts);
* - list of the last N blocks of data with checksum, for deduplication (/blocks);
* - the list of incremental block numbers (/block_numbers) that we are about to insert,
* to ensure the linear order of data insertion and data merge only on the intervals in this sequence;
* - coordinates writes with quorum (/quorum).
* - coordinate writes with quorum (/quorum).
* - Storage of mutation entries (ALTER DELETE, ALTER UPDATE etc.) to execute (/mutations).
* See comments in StorageReplicatedMergeTree::mutate() for details.
*/
@ -65,6 +66,8 @@ namespace DB
* - if the part is corrupt (removePartAndEnqueueFetch) or absent during the check (at start - checkParts, while running - searchForMissingPart),
* actions are put on GET from other replicas;
*
* TODO Update the GET part after rewriting the code (search locally).
*
* The replica to which INSERT was made in the queue will also have an entry of the GET of this data.
* Such an entry is considered to be executed as soon as the queue handler sees it.
*