lmdb - npm Package Compare versions

Comparing version 1.6.6 to 1.6.7

assets/performance.png

package.json

		{
		"name": "lmdb",
		"author": "Kris Zyp",
		"version": "1.6.6",
		"version": "1.6.7",
		"description": "Simple, efficient, scalable data store wrapper for LMDB",
		@@ -48,3 +48,3 @@ "license": "MIT",
		"devDependencies": {
		"@types/node": "latest",
		"@types/node": "^16.7.10",
		"benchmark": "^2.1.4",
		@@ -51,0 +51,0 @@ "chai": "^4.3.4",

README.md

		@@ -16,2 +16,4 @@ [![license](https://img.shields.io/badge/license-MIT-brightgreen)](LICENSE)

		<a href="https://github.com/kriszyp/db-benchmark"><img src="./assets/performance.png" width="700"/></a>

		Benchmarking on Node 14.9, with 3.4Ghz i7-4770 Windows, a get operation, using JS numbers as a key, retrieving data from the database (random access), and decoding the data into a structured object with 10 properties (using default [MessagePack encoding](https://github.com/kriszyp/msgpackr)), can be done in about half a microsecond, or about 1,900,000/sec on a single thread. This is almost three times as fast as a single native `JSON.parse` call with the same object without any DB interaction! LMDB scales effortlessly across multiple processes or threads; over 6,000,000 operations/sec on the same 4/8 core computer by running across multiple threads (or 18,000,000 operations/sec with raw binary data). By running writes on a separate transactional thread, writing is extremely fast as well. With encoding the same objects, full encoding and writes can be performed at about 500,000 puts/second or 1,700,000 puts/second on multiple threads.
		@@ -224,3 +226,3 @@
		### `store.openDB(database: string\|{name:string,...})`
		LMDB supports multiple databases per environment (an environment is a single memory-mapped file). When you initialize an LMDB store with `open`, the store uses the default root database. However, you can use multiple databases per environment/file and instantiate a store for each one. If you are going to be opening many databases, make sure you set the `maxDbs` (it defaults to 12). For example, we can open multiple stores for a single environment:
		LMDB supports multiple databases per environment (an environment corresponds to a single memory-mapped file). When you initialize an LMDB store with `open`, the store uses the default root database. However, you can use multiple databases per environment/file and instantiate a store for each one. If you are going to be opening many databases, make sure you set the `maxDbs` (it defaults to 12). For example, we can open multiple stores for a single environment:
		```
		@@ -239,3 +241,3 @@ const { open } = require('lmdb');
		Both these puts will be batched and committed in the same transaction in the next event turn.
		Also, you can start a transaction from one store and make writes from any of the stores in that same environment (and they will be a part of the same transaction:
		Also, you can start a transaction from one store and make writes from any of the stores in that same environment (and they will be a part of the same transaction):
		```
		@@ -257,2 +259,8 @@ rootStore.transactionAsync(() => {

		### `store.getBinary(key): Buffer`
		This will retrieve the binary data at the specified key. This is just like `get`, except it will always return the value's binary representation as a buffer, rather than decoding with the store's encoding format (if there is no entry, `undefined` will still be returned).

		### `store.getBinaryFast(key): Buffer`
		This will retrieve the binary data at the specified key, like `getBinary`, except it uses reusable buffers, which is faster, but means the data in the buffer is only valid until the next get operation (including cursor operations).

		### `resetReadTxn(): void`
		@@ -259,0 +267,0 @@ Normally, this library will automatically start a reader transaction for get and range operations, periodically reseting the read transaction on new event turns and after any write transactions are committed, to ensure it is using an up-to-date snapshot of the database. However, you can call `resetReadTxn` if you need to manually force the read transaction to reset to the latest snapshot/version of the database. In particular, this may be useful running with multiple processes where you need to immediately reset the read transaction based on a known update in another process (rather than waiting for the next event turn).

test/index.test.js

		@@ -427,2 +427,8 @@ 'use strict';
		count.should.equal(2);
		});
		it('should count ordered-binary dupsort query with start/end', async function() {
		db3.put('key1', 1);
		db3.put('key1', 2);
		db3.put('key1', 3);
		await db3.put('key2', 3);
		db3.getValuesCount('key1').should.equal(3);
		@@ -437,2 +443,49 @@ db3.getValuesCount('key1', { start: 1, end: 3 }).should.equal(2);
		});
		it('should reverse iterate ordered-binary dupsort query with start/end', async function() {
		db3.put('key1', 1);
		db3.put('key1', 2);
		db3.put('key1', 3);
		await db3.put('key2', 3);
		let count = 0;
		for (let value of db3.getValues('key1', { reverse: true, start: 2 })) {
		count++;
		value.should.equal(3 - count);
		}
		count.should.equal(2);

		count = 0;
		for (let value of db3.getValues('key1', { reverse: true, start: 2.5 })) {
		count++;
		value.should.equal(3 - count);
		}
		count.should.equal(2);

		count = 0;
		for (let value of db3.getValues('key1', { reverse: true, start: 50 })) {
		count++;
		value.should.equal(4 - count);
		}
		count.should.equal(3);

		count = 0;
		for (let value of db3.getValues('key1', { reverse: true, start: 2, end: 1 })) {
		count++;
		value.should.equal(3 - count);
		}
		count.should.equal(1);

		count = 0;
		for (let value of db3.getValues('key1', { reverse: true, end: 1 })) {
		count++;
		value.should.equal(4 - count);
		}
		count.should.equal(2);

		count = 0;
		for (let value of db3.getValues('key1', { reverse: true, start: 0.5 })) {
		count++;
		}
		count.should.equal(0);

		});
		it('doesExist', async function() {
		@@ -559,3 +612,3 @@ let data1 = {foo: 1, bar: true}
		});
		it.skip('big child transactions', async function() {
		it('big child transactions', async function() {
		let ranTransaction
		@@ -567,8 +620,5 @@ db.put('key1', 'async initial value'); // should be queued for async write, but should put before queued transaction
		let value
		for (let i = 0; i < 4; i++) {
		value += ' test string ' + value
		for (let i = 0; i < 5000; i++) {
		db.put('key' + i, 'test')
		}
		for (let i = 0; i < 4000; i++) {
		db.put('key' + i, value)
		}
		})
		@@ -575,0 +625,0 @@ await db.put('key1', 'test');

dependencies/lmdb/libraries/liblmdb/mdb.c