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@jboner
jboner / latency.txt
Last active July 27, 2024 12:32
Latency Numbers Every Programmer Should Know
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
@rgreenjr
rgreenjr / postgres_queries_and_commands.sql
Last active July 27, 2024 16:50
Useful PostgreSQL Queries and Commands
-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query
FROM pg_stat_activity
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%'
ORDER BY query_start desc;
-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query
FROM pg_stat_activity
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%'
@KartikTalwar
KartikTalwar / Documentation.md
Last active June 25, 2024 10:55
Rsync over SSH - (40MB/s over 1GB NICs)

The fastest remote directory rsync over ssh archival I can muster (40MB/s over 1gb NICs)

This creates an archive that does the following:

rsync (Everyone seems to like -z, but it is much slower for me)

  • a: archive mode - rescursive, preserves owner, preserves permissions, preserves modification times, preserves group, copies symlinks as symlinks, preserves device files.
  • H: preserves hard-links
  • A: preserves ACLs
@colinvh
colinvh / aws.md
Last active July 22, 2024 10:24
AWS Region Names

Alternative naming schemes for AWS regions

Purpose

The intent is to define terse, standards-supported names for AWS regions.

Schemes

@DocX
DocX / README.md
Last active September 5, 2023 12:58
Connect to bash inside running ECS container by cluster and service name
@magnetikonline
magnetikonline / README.md
Last active July 27, 2024 01:39
List all Git repository objects by size.

List all Git repository objects by size

Summary

Bash script which will:

  • Iterate all commits made within a Git repository.
@rylev
rylev / learn.md
Created March 5, 2019 10:50
How to Learn Rust

Learning Rust

The following is a list of resources for learning Rust as well as tips and tricks for learning the language faster.

Warning

Rust is not C or C++ so the way your accustomed to do things in those languages might not work in Rust. The best way to learn Rust is to embrace its best practices and see where that takes you.

The generally recommended path is to start by reading the books, and doing small coding exercises until the rules around borrow checking become intuitive. Once this happens, then you can expand to more real world projects. If you find yourself struggling hard with the borrow checker, seek help. It very well could be that you're trying to solve your problem in a way that goes against how Rust wants you to work.