##// END OF EJS Templates
localrepo: experimental support for non-zlib revlog compression...
localrepo: experimental support for non-zlib revlog compression The final part of integrating the compression manager APIs into revlog storage is the plumbing for repositories to advertise they are using non-zlib storage and for revlogs to instantiate a non-zlib compression engine. The main intent of the compression manager work was to zstd all of the things. Adding zstd to revlogs has proved to be more involved than other places because revlogs are... special. Very small inputs and the use of delta chains (which are themselves a form of compression) are a completely different use case from streaming compression, which bundles and the wire protocol employ. I've conducted numerous experiments with zstd in revlogs and have yet to formalize compression settings and a storage architecture that I'm confident I won't regret later. In other words, I'm not yet ready to commit to a new mechanism for using zstd - or any other compression format - in revlogs. That being said, having some support for zstd (and other compression formats) in revlogs in core is beneficial. It can allow others to conduct experiments. This patch introduces *highly experimental* support for non-zlib compression formats in revlogs. Introduced is a config option to control which compression engine to use. Also introduced is a namespace of "exp-compression-*" requirements to denote support for non-zlib compression in revlogs. I've prefixed the namespace with "exp-" (short for "experimental") because I'm not confident of the requirements "schema" and in no way want to give the illusion of supporting these requirements in the future. I fully intend to drop support for these requirements once we figure out what we're doing with zstd in revlogs. A good portion of the patch is teaching the requirements system about registered compression engines and passing the requested compression engine as an opener option so revlogs can instantiate the proper compression engine for new operations. That's a verbose way of saying "we can now use zstd in revlogs!" On an `hg pull` conversion of the mozilla-unified repo with no extra redelta settings (like aggressivemergedeltas), we can see the impact of zstd vs zlib in revlogs: $ hg perfrevlogchunks -c ! chunk ! wall 2.032052 comb 2.040000 user 1.990000 sys 0.050000 (best of 5) ! wall 1.866360 comb 1.860000 user 1.820000 sys 0.040000 (best of 6) ! chunk batch ! wall 1.877261 comb 1.870000 user 1.860000 sys 0.010000 (best of 6) ! wall 1.705410 comb 1.710000 user 1.690000 sys 0.020000 (best of 6) $ hg perfrevlogchunks -m ! chunk ! wall 2.721427 comb 2.720000 user 2.640000 sys 0.080000 (best of 4) ! wall 2.035076 comb 2.030000 user 1.950000 sys 0.080000 (best of 5) ! chunk batch ! wall 2.614561 comb 2.620000 user 2.580000 sys 0.040000 (best of 4) ! wall 1.910252 comb 1.910000 user 1.880000 sys 0.030000 (best of 6) $ hg perfrevlog -c -d 1 ! wall 4.812885 comb 4.820000 user 4.800000 sys 0.020000 (best of 3) ! wall 4.699621 comb 4.710000 user 4.700000 sys 0.010000 (best of 3) $ hg perfrevlog -m -d 1000 ! wall 34.252800 comb 34.250000 user 33.730000 sys 0.520000 (best of 3) ! wall 24.094999 comb 24.090000 user 23.320000 sys 0.770000 (best of 3) Only modest wins for the changelog. But manifest reading is significantly faster. What's going on? One reason might be data volume. zstd decompresses faster. So given more bytes, it will put more distance between it and zlib. Another reason is size. In the current design, zstd revlogs are *larger*: debugcreatestreamclonebundle (size in bytes) zlib: 1,638,852,492 zstd: 1,680,601,332 I haven't investigated this fully, but I reckon a significant cause of larger revlogs is that the zstd frame/header has more bytes than zlib's. For very small inputs or data that doesn't compress well, we'll tend to store more uncompressed chunks than with zlib (because the compressed size isn't smaller than original). This will make revlog reading faster because it is doing less decompression. Moving on to bundle performance: $ hg bundle -a -t none-v2 (total CPU time) zlib: 102.79s zstd: 97.75s So, marginal CPU decrease for reading all chunks in all revlogs (this is somewhat disappointing). $ hg bundle -a -t <engine>-v2 (total CPU time) zlib: 191.59s zstd: 115.36s This last test effectively measures the difference between zlib->zlib and zstd->zstd for revlogs to bundle. This is a rough approximation of what a server does during `hg clone`. There are some promising results for zstd. But not enough for me to feel comfortable advertising it to users. We'll get there...

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mercurial.js
439 lines | 12.1 KiB | application/javascript | JavascriptLexer
// mercurial.js - JavaScript utility functions
//
// Rendering of branch DAGs on the client side
// Display of elapsed time
// Show or hide diffstat
//
// Copyright 2008 Dirkjan Ochtman <dirkjan AT ochtman DOT nl>
// Copyright 2006 Alexander Schremmer <alex AT alexanderweb DOT de>
//
// derived from code written by Scott James Remnant <scott@ubuntu.com>
// Copyright 2005 Canonical Ltd.
//
// This software may be used and distributed according to the terms
// of the GNU General Public License, incorporated herein by reference.
var colors = [
[ 1.0, 0.0, 0.0 ],
[ 1.0, 1.0, 0.0 ],
[ 0.0, 1.0, 0.0 ],
[ 0.0, 1.0, 1.0 ],
[ 0.0, 0.0, 1.0 ],
[ 1.0, 0.0, 1.0 ]
];
function Graph() {
this.canvas = document.getElementById('graph');
if (window.G_vmlCanvasManager) this.canvas = window.G_vmlCanvasManager.initElement(this.canvas);
this.ctx = this.canvas.getContext('2d');
this.ctx.strokeStyle = 'rgb(0, 0, 0)';
this.ctx.fillStyle = 'rgb(0, 0, 0)';
this.cur = [0, 0];
this.line_width = 3;
this.bg = [0, 4];
this.cell = [2, 0];
this.columns = 0;
this.revlink = '';
this.reset = function() {
this.bg = [0, 4];
this.cell = [2, 0];
this.columns = 0;
document.getElementById('nodebgs').innerHTML = '';
document.getElementById('graphnodes').innerHTML = '';
}
this.scale = function(height) {
this.bg_height = height;
this.box_size = Math.floor(this.bg_height / 1.2);
this.cell_height = this.box_size;
}
this.setColor = function(color, bg, fg) {
// Set the colour.
//
// If color is a string, expect an hexadecimal RGB
// value and apply it unchanged. If color is a number,
// pick a distinct colour based on an internal wheel;
// the bg parameter provides the value that should be
// assigned to the 'zero' colours and the fg parameter
// provides the multiplier that should be applied to
// the foreground colours.
var s;
if(typeof color == "string") {
s = "#" + color;
} else { //typeof color == "number"
color %= colors.length;
var red = (colors[color][0] * fg) || bg;
var green = (colors[color][1] * fg) || bg;
var blue = (colors[color][2] * fg) || bg;
red = Math.round(red * 255);
green = Math.round(green * 255);
blue = Math.round(blue * 255);
s = 'rgb(' + red + ', ' + green + ', ' + blue + ')';
}
this.ctx.strokeStyle = s;
this.ctx.fillStyle = s;
return s;
}
this.edge = function(x0, y0, x1, y1, color, width) {
this.setColor(color, 0.0, 0.65);
if(width >= 0)
this.ctx.lineWidth = width;
this.ctx.beginPath();
this.ctx.moveTo(x0, y0);
this.ctx.lineTo(x1, y1);
this.ctx.stroke();
}
this.render = function(data) {
var backgrounds = '';
var nodedata = '';
for (var i in data) {
var parity = i % 2;
this.cell[1] += this.bg_height;
this.bg[1] += this.bg_height;
var cur = data[i];
var node = cur[1];
var edges = cur[2];
var fold = false;
var prevWidth = this.ctx.lineWidth;
for (var j in edges) {
line = edges[j];
start = line[0];
end = line[1];
color = line[2];
var width = line[3];
if(width < 0)
width = prevWidth;
var branchcolor = line[4];
if(branchcolor)
color = branchcolor;
if (end > this.columns || start > this.columns) {
this.columns += 1;
}
if (start == this.columns && start > end) {
var fold = true;
}
x0 = this.cell[0] + this.box_size * start + this.box_size / 2;
y0 = this.bg[1] - this.bg_height / 2;
x1 = this.cell[0] + this.box_size * end + this.box_size / 2;
y1 = this.bg[1] + this.bg_height / 2;
this.edge(x0, y0, x1, y1, color, width);
}
this.ctx.lineWidth = prevWidth;
// Draw the revision node in the right column
column = node[0]
color = node[1]
radius = this.box_size / 8;
x = this.cell[0] + this.box_size * column + this.box_size / 2;
y = this.bg[1] - this.bg_height / 2;
var add = this.vertex(x, y, color, parity, cur);
backgrounds += add[0];
nodedata += add[1];
if (fold) this.columns -= 1;
}
document.getElementById('nodebgs').innerHTML += backgrounds;
document.getElementById('graphnodes').innerHTML += nodedata;
}
}
function process_dates(parentSelector){
// derived from code from mercurial/templatefilter.py
var scales = {
'year': 365 * 24 * 60 * 60,
'month': 30 * 24 * 60 * 60,
'week': 7 * 24 * 60 * 60,
'day': 24 * 60 * 60,
'hour': 60 * 60,
'minute': 60,
'second': 1
};
function format(count, string){
var ret = count + ' ' + string;
if (count > 1){
ret = ret + 's';
}
return ret;
}
function shortdate(date){
var ret = date.getFullYear() + '-';
// getMonth() gives a 0-11 result
var month = date.getMonth() + 1;
if (month <= 9){
ret += '0' + month;
} else {
ret += month;
}
ret += '-';
var day = date.getDate();
if (day <= 9){
ret += '0' + day;
} else {
ret += day;
}
return ret;
}
function age(datestr){
var now = new Date();
var once = new Date(datestr);
if (isNaN(once.getTime())){
// parsing error
return datestr;
}
var delta = Math.floor((now.getTime() - once.getTime()) / 1000);
var future = false;
if (delta < 0){
future = true;
delta = -delta;
if (delta > (30 * scales.year)){
return "in the distant future";
}
}
if (delta > (2 * scales.year)){
return shortdate(once);
}
for (unit in scales){
var s = scales[unit];
var n = Math.floor(delta / s);
if ((n >= 2) || (s == 1)){
if (future){
return format(n, unit) + ' from now';
} else {
return format(n, unit) + ' ago';
}
}
}
}
var nodes = document.querySelectorAll((parentSelector || '') + ' .age');
var dateclass = new RegExp('\\bdate\\b');
for (var i=0; i<nodes.length; ++i){
var node = nodes[i];
var classes = node.className;
var agevalue = age(node.textContent);
if (dateclass.test(classes)){
// We want both: date + (age)
node.textContent += ' ('+agevalue+')';
} else {
node.title = node.textContent;
node.textContent = agevalue;
}
}
}
function toggleDiffstat() {
var curdetails = document.getElementById('diffstatdetails').style.display;
var curexpand = curdetails == 'none' ? 'inline' : 'none';
document.getElementById('diffstatdetails').style.display = curexpand;
document.getElementById('diffstatexpand').style.display = curdetails;
}
function toggleLinewrap() {
function getLinewrap() {
var nodes = document.getElementsByClassName('sourcelines');
// if there are no such nodes, error is thrown here
return nodes[0].classList.contains('wrap');
}
function setLinewrap(enable) {
var nodes = document.getElementsByClassName('sourcelines');
for (var i = 0; i < nodes.length; i++) {
if (enable) {
nodes[i].classList.add('wrap');
} else {
nodes[i].classList.remove('wrap');
}
}
var links = document.getElementsByClassName('linewraplink');
for (var i = 0; i < links.length; i++) {
links[i].innerHTML = enable ? 'on' : 'off';
}
}
setLinewrap(!getLinewrap());
}
function format(str, replacements) {
return str.replace(/%(\w+)%/g, function(match, p1) {
return String(replacements[p1]);
});
}
function makeRequest(url, method, onstart, onsuccess, onerror, oncomplete) {
xfr = new XMLHttpRequest();
xfr.onreadystatechange = function() {
if (xfr.readyState === 4) {
try {
if (xfr.status === 200) {
onsuccess(xfr.responseText);
} else {
throw 'server error';
}
} catch (e) {
onerror(e);
} finally {
oncomplete();
}
}
};
xfr.open(method, url);
xfr.overrideMimeType("text/xhtml; charset=" + document.characterSet.toLowerCase());
xfr.send();
onstart();
return xfr;
}
function removeByClassName(className) {
var nodes = document.getElementsByClassName(className);
while (nodes.length) {
nodes[0].parentNode.removeChild(nodes[0]);
}
}
function docFromHTML(html) {
var doc = document.implementation.createHTMLDocument('');
doc.documentElement.innerHTML = html;
return doc;
}
function appendFormatHTML(element, formatStr, replacements) {
element.insertAdjacentHTML('beforeend', format(formatStr, replacements));
}
function ajaxScrollInit(urlFormat,
nextPageVar,
nextPageVarGet,
containerSelector,
messageFormat,
mode) {
updateInitiated = false;
container = document.querySelector(containerSelector);
function scrollHandler() {
if (updateInitiated) {
return;
}
var scrollHeight = document.documentElement.scrollHeight;
var clientHeight = document.documentElement.clientHeight;
var scrollTop = document.body.scrollTop
|| document.documentElement.scrollTop;
if (scrollHeight - (scrollTop + clientHeight) < 50) {
updateInitiated = true;
removeByClassName('scroll-loading-error');
container.lastElementChild.classList.add('scroll-separator');
if (!nextPageVar) {
var message = {
'class': 'scroll-loading-info',
text: 'No more entries'
};
appendFormatHTML(container, messageFormat, message);
return;
}
makeRequest(
format(urlFormat, {next: nextPageVar}),
'GET',
function onstart() {
var message = {
'class': 'scroll-loading',
text: 'Loading...'
};
appendFormatHTML(container, messageFormat, message);
},
function onsuccess(htmlText) {
if (mode == 'graph') {
var sizes = htmlText.match(/^\s*<canvas id="graph" width="(\d+)" height="(\d+)"><\/canvas>$/m);
var addWidth = sizes[1];
var addHeight = sizes[2];
addWidth = parseInt(addWidth);
addHeight = parseInt(addHeight);
graph.canvas.width = addWidth;
graph.canvas.height = addHeight;
var dataStr = htmlText.match(/^\s*var data = (.*);$/m)[1];
var data = JSON.parse(dataStr);
if (data.length < nextPageVar) {
nextPageVar = undefined;
}
graph.reset();
graph.render(data);
} else {
var doc = docFromHTML(htmlText);
var nodes = doc.querySelector(containerSelector).children;
var curClass = 'c' + Date.now();
while (nodes.length) {
var node = nodes[0];
node = document.adoptNode(node);
node.classList.add(curClass);
container.appendChild(node);
}
process_dates('.' + curClass);
}
nextPageVar = nextPageVarGet(htmlText, nextPageVar);
},
function onerror(errorText) {
var message = {
'class': 'scroll-loading-error',
text: 'Error: ' + errorText
};
appendFormatHTML(container, messageFormat, message);
},
function oncomplete() {
removeByClassName('scroll-loading');
updateInitiated = false;
scrollHandler();
}
);
}
}
window.addEventListener('scroll', scrollHandler);
window.addEventListener('resize', scrollHandler);
scrollHandler();
}
document.addEventListener('DOMContentLoaded', function() {
process_dates();
}, false);