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Oleksandr Kulychok kool79

  • Astound Commerce
  • Ukraine, Vinnitsa
  • 15:57 (UTC +02:00)
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kool79 / latency.txt
Created February 15, 2019 16:35 — forked from jboner/latency.txt
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
@kool79
kool79 / reuse-code.js
Created February 19, 2021 17:02 — forked from JamesMessinger/reuse-code.js
Saving JavaScript code to a variable in Postman
// Save common tests in a global variable
postman.setGlobalVariable("commonTests", () => {
// The Content-Type must be JSON
tests["Content-Type header is set"] = postman.getResponseHeader("Content-Type") === "application/json";
// The response time must be less than 500 milliseconds
tests["Response time is acceptable"] = responseTime < 500;
// The response body must include an "id" property
var data = JSON.parse(responseBody);
@kool79
kool79 / crypto-aes-256-gcm-demo.js
Created February 19, 2021 23:51 — forked from rjz/crypto-aes-256-gcm-demo.js
example using node.js crypto API with aes-256-gcm
const buffer = require('buffer');
const crypto = require('crypto');
// Demo implementation of using `aes-256-gcm` with node.js's `crypto` lib.
const aes256gcm = (key) => {
const ALGO = 'aes-256-gcm';
// encrypt returns base64-encoded ciphertext
const encrypt = (str) => {
// Hint: the `iv` should be unique (but not necessarily random).
@kool79
kool79 / ExcelToTable.java
Created August 10, 2023 02:39 — forked from ejwinter/ExcelToTable.java
Turn an Excel (xlsx) file with a single table in it into a Guava table with a header indexed
/**
* This class takes an Excel spreadsheet and converts it into a Guava Table format.
* When other formats of the file are to be supported (like CSV, TSV etc.,) implement the apply method with that format.
*/
@Component
public class ExcelToTableLoader implements TableGenerator<File> {
private static final Logger logger = org.slf4j.LoggerFactory.getLogger(ExcelToTableLoader.class);