1、the clickhouse version is 20.1.6.30,settings distributed_product_mode=local;max_threads=auto.;
2、in distribute node's clickhouse-client ,I SET max_result_rows = 81920,max_result_bytes=102400000, result_overflow_mode = 'break';max_block_size is default values 65536.
then run the query: select s_ip,count()counts from ds_ods.iptable group by s_ip order by counts desc limit 500;
on one of the datanode,query the query's qeury_log,can see the following result:,my questions is that why the datanode's result_rows is 11073720,but not the value 81920 I set or 65536*2. It seems that max_result_rows doesn't work on remote servers.is there a method that can limit the result of the local nodethat return to the distributed node?
type: QueryFinish
event_date: 2020-05-11
event_time: 2020-05-11 11:16:02
query_start_time: 2020-05-11 11:15:54
query_duration_ms: 14261
read_rows: 104054038
read_bytes: 2311618357
written_rows: 0
written_bytes: 0
result_rows: 11073720
result_bytes: 334685660
memory_usage: 3824731963
query: SELECT s_ip, count() AS counts FROM ods.iptables_local GROUP BY s_ip ORDER BY counts ASC
exception:
stack_trace:
is_initial_query: 0
user: default
query_id: 9f86b4db-cce7-4f13-8609-0ac048206760
address: ::ffff:172.24.9.49
port: 65106
initial_user: writer
initial_query_id: 64622f08-3ed9-435b-a087-87dfed405d4f
initial_address: ::ffff:172.24.9.49
initial_port: 43820
interface: 1
os_user: root
client_hostname: platform-server-5
client_name: ClickHouse client
client_revision: 54431
client_version_major: 20
client_version_minor: 1
client_version_patch: 6
http_method: 0
http_user_agent:
quota_key:
revision: 54431
thread_numbers: [329,79,302,90,266,294,103,106,78,77,125,120,293,119,95,124,117,67]
os_thread_ids: [27498,31790,27269,7048,26996,27262,7067,7061,31791,31792,7084,7081,27261,7060,7056,7082,7063,14399]
ProfileEvents.Names: ['Query','SelectQuery','FileOpen','Seek','ReadBufferFromFileDescriptorRead','ReadBufferFromFileDescriptorReadBytes','ReadCompressedBytes','CompressedReadBufferBlocks','CompressedReadBufferBytes','IOBufferAllocs','IOBufferAllocBytes','ArenaAllocChunks','ArenaAllocBytes','MarkCacheHits','CreatedReadBufferOrdinary','DiskReadElapsedMicroseconds','NetworkSendElapsedMicroseconds','SelectedParts','SelectedRanges','SelectedMarks','ContextLock','RWLockAcquiredReadLocks','RealTimeMicroseconds','UserTimeMicroseconds','SystemTimeMicroseconds','SoftPageFaults','OSCPUWaitMicroseconds','OSCPUVirtualTimeMicroseconds','OSWriteBytes','OSReadChars','OSWriteChars']
ProfileEvents.Values: [1,1,98,11,587,517022008,513673783,13552,1479186063,198,79219423,112,536838144,98,98,269456,350581,88,88,13798,40,1,104897887,60187046,4483097,1062755,2447226,64669016,4096,517023744,28672]
Settings.Names: ['queue_max_wait_ms','use_uncompressed_cache','background_pool_size','load_balancing','skip_unavailable_shards','log_queries','distributed_product_mode','max_result_rows','max_result_bytes','result_overflow_mode','max_execution_time','timeout_overflow_mode','max_memory_usage','max_memory_usage_for_user','max_memory_usage_for_all_queries','send_logs_level','allow_experimental_data_skipping_indices']
Settings.Values: ['0','1','32','random','1','1','local','81920','102400000','break','300','throw','100000000000','180000000000','180000000000','trace','1']
3、Here is the doc:.And in the settings.h can see this code:M(SettingUInt64, max_result_rows, 0, "Limit on result size in rows. Also checked for intermediate data sent from remote servers.", 0).It means it will limit the intermediate data size in rows from remote servers?