siracusa

From Jonathan Dietz, Jr.:

Almost all new displays employ VESA Coordinated Video Timings using Reduced Blanking Timing Version 2 (CVT-RBv2) which adds a small amount of overhead to the video signal. This overhead includes 80 additional horizontal pixels and enough additional lines to meet the 460 µs minimum vertical blanking interval requirement. You can download an Excel spreadsheet from VESA that will do all the calculations for you, but the math is pretty simple:

460 / ((1000000 / [refresh rate in Hz] - 460) / [vertical resolution])

To get an integer number of lines, you round this result down and add 1. So for Pro Display XDR resolution at 120 Hz that would work out to:

460 / (1000000 / 120 - 460) / 3384) = 197.710 = 198 additional lines

yurishkuro

• What do Etcd, Consul, and Zookeeper do?
  • Service Registration:
    • Host, port number, and sometimes authentication credentials, protocols, versions numbers, and/or environment details.
  • Service Discovery:
    • Ability for client application to query the central registry to learn of service location.
  • Consistent and durable general-purpose K/V store across distributed system.
    • Some solutions support this better than others.
    • Based on Paxos or some derivative (i.e. Raft) algorithm to quickly converge to a consistent state.
• Centralized locking can be based on this K/V store.

jasonswearingen

/** 

WHAT:  A very simple example of redux + redux-simple-router using Typescript.

WHY: The official example found here: https://github.com/rackt/redux-simple-router/tree/1.0.2/examples/basic has problems:
1) it is spread over many files making it very hard to "skim"
2) it is organized by function, not by feature.  (Example: learning "how to manipulate redux state" is spread over 5 files in 4 folders)
3) there are no comments explaining what's going on/why.

WHO: by [email protected]

seboudry

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns                     on recent CPU
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 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 4X memory

jelies

package com.jelies.spring3tomcat7.repository;

import org.hibernate.Criteria;
import org.hibernate.ScrollableResults;
import org.hibernate.StatelessSession;
import org.hibernate.Transaction;
import org.hibernate.criterion.Order;
import org.hibernate.criterion.Restrictions;
import org.joda.time.LocalDate;
import org.springframework.beans.factory.annotation.Autowired;