DanielHons

/*
  Given a table containing at least a column for the number of errors (with no success in between) and 
  frequently calling the following select will provide the candidates for a retry using an exponential backoff.
*/

SELECT * FROM retryable_error WHERE 
  CURRENT_TIMESTAMP > (last_retry + CAST(CONCAT(CAST(POWER(2, error_count) AS text), 's') AS INTERVAL))

ololobus

\set aid random(1, 100000 * :scale)
\set bid random(1, 1 * :scale)
\set tid random(1, 10 * :scale)
\set delta random(-5000, 5000)
BEGIN;
UPDATE pgbench_accounts SET abalance = abalance + :delta WHERE aid = :aid;
SELECT abalance FROM pgbench_accounts WHERE aid = :aid;
UPDATE pgbench_tellers SET tbalance = tbalance + :delta WHERE tid = :tid;
UPDATE pgbench_branches SET bbalance = bbalance + :delta WHERE bid = :bid;
INSERT INTO pgbench_history (tid, bid, aid, delta, mtime) VALUES (:tid, :bid, :aid, :delta, CURRENT_TIMESTAMP);

lukasnellen

Configuration to use remote tmux over ssh in iterm

This is a compilation of information I found in different postings on the net.

All manual invocation

Basic remote tmux session

tmux can be invoked in command mode using tmux -CC. The simplest way to get a remote tmux session into a window of iterm is to invoke it on the remote host

jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD