- Материалы для подготовки к собеседованию:
- Yandex.Tank wiki:
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
I hereby claim:
To claim this, I am signing this object:
Sometimes you may want to undo a whole commit with all changes. Instead of going through all the changes manually, you can simply tell git to revert a commit, which does not even have to be the last one. Reverting a commit means to create a new commit that undoes all changes that were made in the bad commit. Just like above, the bad commit remains there, but it no longer affects the the current master and any future commits on top of it.
git revert {commit_id}
Deleting the last commit is the easiest case. Let's say we have a remote origin with branch master that currently points to commit dd61ab32. We want to remove the top commit. Translated to git terminology, we want to force the master branch of the origin remote repository to the parent of dd61ab32:
#!/bin/bash | |
# To create in [.babun/]cygwin/usr/local/bin/subl with chmod +x | |
ARGS="" | |
while test $# -gt 0 | |
do | |
ARGS="$ARGS ${1#/cygdrive/[a-zA-Z]}"; # Remove /cygdrive and disk letter from the path | |
shift | |
done |
title: "Improving Performance" description: "" project: "riak_kv" project_version: "2.2.3" menu: riak_kv-2.2.3: name: "Performance" identifier: "managing_performance" weight: 206
title: "Open Files Limit" description: "" project: "riak_kv" project_version: "2.2.3" menu: riak_kv-2.2.3: name: "Open Files Limit" identifier: "performance_open_files_limit" weight: 101