## 2018-06-27 Measurements

fatcat_prod=# select count(*) from release_ident; 20983019
fatcat_prod=# select count(*) from work_ident; 20988140
fatcat_prod=# select count(*) from file_ident; 1482335
fatcat_prod=# select count(*) from creator_ident; 4167419
fatcat_prod=# select count(*) from container_ident; 61793

select count(*) from release_contrib; 59798133

bnewbold@wbgrp-svc500$ sudo du -sh /var/lib/postgresql/
43G

running import-crossref with 20 threads, and manifest importer with one (at 33%
complete). had already imported ~7million works+releases previously.


 PostgreSQL 10.4 - wbgrp-svc500.us.archive.org - postgres@localhost:5432/postgre
  Size:   41.38G -   323.40K/s        | TPS:         885
  Mem.:   50.80% -    23.86G/49.14G   | IO Max:    79539/s
  Swap:    0.80% -   408.89M/50.00G   | Read :     67.04K/s -     16/s
  Load:    6.69 7.41 7.69             | Write:      1.93M/s -    493/s


----total-cpu-usage---- -dsk/total- -net/total- ---paging-- ---system--
usr sys idl wai hiq siq| read  writ| recv  send|  in   out | int   csw 
 32   6  62   0   0   0| 296k 3880k| 334k 3144B|   0     0 |  21k   65k
 31   6  62   0   0   0|   0  3072k| 391k  318B|   0     0 |  51k  141k
 31   6  63   0   0   0|  16k 1080k| 344k 1988B|   0     0 |  35k  104k
 29   6  65   0   0   0| 136k 2608k| 175k  332B|   0     0 |9835    15k
 28   5  67   0   0   0| 408k 4368k| 285k  832B|   0     0 |  14k   17k
 33   5  62   0   0   0|  56k 3256k| 219k   99B|   0     0 |  22k   49k
 31   6  63   0   0   0| 188k 5120k| 158k  318B|   0     0 |  17k   29k
 30   6  64   0   0   0| 200k 6984k| 239k  988B|   0     0 |  16k   24k
 30   6  64   0   0   0| 168k 5504k| 159k  152B|   0     0 |  14k   20k
 28   7  65   0   0   0| 440k   12M| 236k  420B|   0     0 |  15k   18k
 29   6  65   0   0   0| 428k 6968k| 352k  310B|   0     0 |  19k   31k
 32   6  62   0   0   0|  64k 3480k| 288k  318B|   0     0 |  18k   55k
 32   6  62   0   0   0|  32k 2080k| 155k  318B|   0     0 |  20k   52k


bnewbold@wbgrp-svc500$ uptime
 22:00:42 up 28 days, 22:31,  6 users,  load average: 7.94, 7.56, 7.72


2018-06-27 21:57:36.102 UTC [401] LOG:  checkpoints are occurring too frequently (13 seconds apart)
2018-06-27 21:57:36.102 UTC [401] HINT:  Consider increasing the configuration parameter "max_wal_size".


     relname     | too_much_seq |      case      |  rel_size   | seq_scan | idx_scan  
-----------------+--------------+----------------+-------------+----------+-----------
 changelog       |      1274670 | Missing Index? |    39411712 |  1274670 |         0
 file_edit       |       612386 | Missing Index? |   108298240 |   612386 |         0
 creator_edit    |       612386 | Missing Index? |   285540352 |   612386 |         0
 container_edit  |       612386 | Missing Index? |     4784128 |   612386 |         0
 release_edit    |       612386 | Missing Index? |  1454489600 |   612386 |         0
 work_edit       |       612386 | Missing Index? |  1454415872 |   612386 |         0
 release_contrib |       296675 | Missing Index? |  4725645312 |   296675 |         0
 release_ref     |       296663 | Missing Index? |  8999837696 |   296663 |         0
 file_release    |         -113 | OK             |    13918208 |      110 |       223
 container_rev   |      -979326 | OK             |    16285696 |       63 |    979389
 file_ident      |     -3671516 | OK             |   109002752 |      362 |   3671878
 file_rev        |     -3944155 | OK             |   302940160 |       95 |   3944250
 creator_rev     |     -8420205 | OK             |   318283776 |     1226 |   8421431
 creator_ident   |     -9525338 | OK             |   309141504 |    52330 |   9577668
 container_ident |    -20581876 | OK             |     4833280 |   272457 |  20854333
 release_ident   |    -40548858 | OK             |  1440948224 |  4160919 |  44709777
 work_rev        |    -42534913 | OK             |  1124671488 |     1161 |  42536074
 editgroup       |    -48864662 | OK             |    34136064 |        1 |  48864663
 work_ident      |    -65008911 | OK             |  1503313920 |     1239 |  65010150
 release_rev     |   -185735794 | OK             | 13649428480 |      128 | 185735922

## Setup

Add to postgres.conf:

    shared_preload_libraries = 'auto_explain,pg_stat_statements'

    # Increase the max size of the query strings Postgres records
    track_activity_query_size = 2048

    # Track statements generated by stored procedures as well
    pg_stat_statements.track = all

Also:
    
    track_counts (already default)
    autovacuum (already default?)
    log_min_error = warning
    log_min_duration_statement = 5000

Then from shell:

    create extension pg_stat_statements;

Regularly want to run:

    VACUUM ANALYZE

## Tuning Values

postgres config:

    max_connections = 100 (default)
    shared_buffers = 128MB -> 10GB (while elastic on same machine; later 16 or more)
    effective_cache_size = 4GB -> 24GB (while elastic on same machine)
    work_mem = 4MB -> 128MB     # relatively few connections/box
    fsync = on
    commit_delay = ??? (and siblings)
    random_page_cost = 1 (for SSD)
    default_statistics_target = 100 -> 200
    maintenance_work_mem = 64MB -> 8GB
    synchronous_commit = off (during dev only! switch to on for production!)
    wal_sync_method (keep default)
    max_wal_size = 64 -> 128 (based on above HINT message)
    # didn't mess with commit_delay/commit_siblings

system:

    sysctl -w vm.overcommit_memory=2
    TODO: ulimit -n 65536
    TODO: ulimit -p 800
        LimitNOFILE
        /lib/systemd/system/postgresql.service

## Resources 

https://www.geekytidbits.com/performance-tuning-postgres/

Could try pgbadger to handle auto_explain type output.

https://www.postgresql.org/docs/10/static/runtime-config-wal.html

IA-specific resources:
    https://git.archive.org/ia/mint/blob/master/postgres/postgres_9_2.yml
    https://git.archive.org/ia/mint/blob/master/postgres/put_datadir_on_ssd.sh
    https://git.archive.org/ia/mint/blob/master/postgres/templates/postgresql.conf.j2