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@brendangregg
brendangregg / dockerpsns.sh
Last active August 23, 2023 10:11
docker ps --namespaces
#!/bin/bash
#
# dockerpsns - proof of concept for a "docker ps --namespaces".
#
# USAGE: ./dockerpsns.sh
#
# This lists containers, their init PIDs, and namespace IDs. If container
# namespaces equal the host namespace, they are colored red (this can be
# disabled by setting color=0 below).
#
@ishubin
ishubin / galen.JavaTestNG.concept.java
Last active August 29, 2015 14:00
A concept of using Galen together with TestNG
import net.mindengine.galen.browser.SeleniumBrowser;
import net.mindengine.galen.browser.Browser;
import net.mindengine.galen.page.Page;
import net.mindengine.galen.specs.page.PageSection;
import net.mindengine.galen.specs.reader.page.PageSpec;
import net.mindengine.galen.specs.reader.page.PageSpecReader;
import net.mindengine.galen.validation.PageValidation;
import net.mindengine.galen.validation.SectionValidation;
import net.mindengine.galen.validation.ValidationError;
import net.mindengine.galen.validation.ValidationListener;

Make it real

Ideas are cheap. Make a prototype, sketch a CLI session, draw a wireframe. Discuss around concrete examples, not hand-waving abstractions. Don't say you did something, provide a URL that proves it.

Ship it

Nothing is real until it's being used by a real user. This doesn't mean you make a prototype in the morning and blog about it in the evening. It means you find one person you believe your product will help and try to get them to use it.

Do it with style

@hellerbarde
hellerbarde / latency.markdown
Created May 31, 2012 13:16 — forked from jboner/latency.txt
Latency numbers every programmer should know

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

@jboner
jboner / latency.txt
Last active June 28, 2025 18:48
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