lesovsky

SELECT 
        now()-pg_postmaster_start_time()    "Uptime", now()-stats_reset     "Since stats reset",
        round(100.0*checkpoints_req/total_checkpoints,1)                    "Forced checkpoint ratio (%)",
        round(np.min_since_reset/total_checkpoints,2)                       "Minutes between checkpoints",
        round(checkpoint_write_time::numeric/(total_checkpoints*1000),2)    "Average write time per checkpoint (s)",
        round(checkpoint_sync_time::numeric/(total_checkpoints*1000),2)     "Average sync time per checkpoint (s)",
        round(total_buffers/np.mp,1)                                        "Total MB written",
        round(buffers_checkpoint/(np.mp*total_checkpoints),2)               "MB per checkpoint",
        round(buffers_checkpoint/(np.mp*np.min_since_reset*60),2)           "Checkpoint MBps",
        round(buffers_clean/(np.mp*np.min_since_reset*60),2)                "Bgwriter MBps",

NikolayS

-- In pg_stat_statements, there is a problem: sometimes (quite often), it registers the same query twice (or even more).
-- It's easy to check in your DB: 
--
--   with heh as (
--     select userid, dbid, query, count(*), array_agg(queryid) queryids
--     from pg_stat_statements group by 1, 2, 3 having count(*) > 1
--  ) select left(query, 85) || '...', userid, dbid, count, queryids from heh;
--
-- This query gives you "full picture", aggregating stats for each query-database-username ternary

benschwarz

Apps

• Postico client for mac
• pgcli - Postgres CLI with autocompletion and syntax highlighting
• pghero - Server and query performance dashboard

Tools

• PEV - Query planning / Explain analyze visualisation
• PostgreSQL's explain analyze made readable

NikolayS

Рекомендации для докладов типа Case Study (компания/проект делится своим опытом)

Недостаточно просто описать задачу в тезисах. Довольно часто бывает так, что заинтересованные слушатели могут это сделать не хуже докладчика. Хорошие же тезисы отличает конкретика: конкретные названия, конкретные числовые показатели (последнее особенно важно для Highload++).

Главное — приоткрыть суть вашего доклада, оставаясь при этом в рамках сжатых тезисов.

И это не так сложно. При подготовке доклада и его тезисов нужно сделать всего лишь три шага.

jberkus

WITH table_scans as (
    SELECT relid,
        tables.idx_scan + tables.seq_scan as all_scans,
        ( tables.n_tup_ins + tables.n_tup_upd + tables.n_tup_del ) as writes,
                pg_relation_size(relid) as table_size
        FROM pg_stat_user_tables as tables
),
all_writes as (
    SELECT sum(writes) as total_writes
    FROM table_scans

sgergely

----- Esc -----
Quick change directory: Esc + c
Quick change directory history: Esc + c and then Esc + h
Quick change directory previous entry: Esc + c and then Esc + p
Command line history: Esc + h
Command line previous command: Esc + p
View change: Esc + t (each time you do this shortcut a new directory view will appear)
Print current working directory in command line: Esc + a
Switch between background command line and MC: Ctrl + o
Search/Go to directory in active panel: Esc + s / Ctrl + s then start typing directory name

jehiah

moved to github --> https://github.com/bill-auger/git-branch-status/