To add onto this message:

Queries are all on the partition key  (select origvalue,ingestdate,mediatype from doc.origdoc where uuid=?). Queries were very fast when the table was <10 million rows.

Table description:

describe doc.origdoc;

CREATE TABLE doc.origdoc (
    uuid text,
    ingestdate timestamp,
    markings text,
    mediatype text,
    origvalue text,
    source text,
    PRIMARY KEY (uuid, ingestdate)
) WITH CLUSTERING ORDER BY (ingestdate ASC)
    AND additional_write_policy = '99p'
    AND bloom_filter_fp_chance = 0.01
    AND caching = {'keys': 'ALL', 'rows_per_partition': 'NONE'}
    AND cdc = false
    AND comment = ''
    AND compaction = {'class': 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy', 'max_threshold': '32', 'min_threshold': '4'}     AND compression = {'chunk_length_in_kb': '16', 'class': 'org.apache.cassandra.io.compress.LZ4Compressor'}
    AND crc_check_chance = 1.0
    AND default_time_to_live = 0
    AND extensions = {}
    AND gc_grace_seconds = 864000
    AND max_index_interval = 2048
    AND memtable_flush_period_in_ms = 0
    AND min_index_interval = 128
    AND read_repair = 'BLOCKING'
    AND speculative_retry = '99p';

-Joe

On 11/29/2021 11:22 AM, Joe Obernberger wrote:
I have an 11 node cluster and am experiencing high read latency on one table.  This table has ~112 million rows:

 nodetool tablehistograms doc.origdoc
doc/origdoc histograms
Percentile      Read Latency     Write Latency SSTables Partition Size        Cell Count
                    (micros) (micros) (bytes)
50%                 36157.19              0.00 1.00 310                 4
75%                 74975.55              0.00 1.00 372                 4
95%                155469.30              0.00 1.00 642                 4
98%                223875.79              0.00 1.00 924                 4
99%                268650.95              0.00 1.00 924                 4
Min                   152.32              0.00 1.00 180                 4
Max                464228.84              0.00 1.00 9887                17

What should I look for to debug?

Thank you!

-Joe

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