performance

问题 Jstat tool gives stats regarding young gc time and full gc time along with other information. As far as I know, Full GC in G1 GC consists of following phases : 1) Concurrent Marking (not Stop the world) 2) Remarking (Stop the world) 3) Reclaimation of empty regions (Stop the world) 4) Reclaimation of partially empty old regions through mixed gc (Happens over the time) Now, I want to know jstat full gc time measures time for which of the phases ? If Phase 1 and 2 are not considered for full gc

问题 I m having one sub child component which is inside a loop of parent component. when one of the sub child components is updating the state of parent component, it is re-rendering the all children since it is loop. How can i avoid the re-render for each iteration. It should update that particular sub child. import React, { useState } from "react"; function Parent() { const [selectedChild, setSelectedChild] = useState([]); const onChangeHandle = (event, id) => { const checked = event.target

问题 I have a scenario to split a large files to small chunks using File Inbound, Splitter, Transformer and File Outbound adapter. I would like to know how long it took to process the file starting from read to split to write back. How do I achieve this functionality? Any help is appreciated. <file:inbound-channel-adapter directory="/Documents" filename-pattern="test.txt" channel="inputFiles"> <int:poller fixed-delay="0"/> </file:inbound-channel-adapter> <int:channel id="inputFiles"> <int

问题 I'm trying to add a far future expires header by editing my .htaccess file this is recommended in the yslow performance rules but when I do, I get a 500 internal server error here's the code I'm using, any body know what's up? ExpiresActive On ExpiresDefault A0 ExpiresByType image/gif A2592000 ExpiresByType image/png A2592000 ExpiresByType image/jpg A2592000 ExpiresByType image/jpeg A2592000 ExpiresByType image/ico A2592000 ExpiresByType text/css A2592000 ExpiresByType text/javascript

问题 I'm trying to add a far future expires header by editing my .htaccess file this is recommended in the yslow performance rules but when I do, I get a 500 internal server error here's the code I'm using, any body know what's up? ExpiresActive On ExpiresDefault A0 ExpiresByType image/gif A2592000 ExpiresByType image/png A2592000 ExpiresByType image/jpg A2592000 ExpiresByType image/jpeg A2592000 ExpiresByType image/ico A2592000 ExpiresByType text/css A2592000 ExpiresByType text/javascript

问题 I'm trying to add a far future expires header by editing my .htaccess file this is recommended in the yslow performance rules but when I do, I get a 500 internal server error here's the code I'm using, any body know what's up? ExpiresActive On ExpiresDefault A0 ExpiresByType image/gif A2592000 ExpiresByType image/png A2592000 ExpiresByType image/jpg A2592000 ExpiresByType image/jpeg A2592000 ExpiresByType image/ico A2592000 ExpiresByType text/css A2592000 ExpiresByType text/javascript

问题 So I'm trying to make a CCG type of game using javafx (similar to Hearthstone), and I was wondering if it's a very bad idea to have one class for each card, because I've done some research and most fan made card games of Hearthstone use JSON to get the card objects. For example if the game only had 4 cards with the names: DragonMaster Vulcan Pirate Chuck Norris I'd have 4 classes, with the names respectively. Now I though this was necessary since every card would have its own behaviour,

问题 So I'm trying to make a CCG type of game using javafx (similar to Hearthstone), and I was wondering if it's a very bad idea to have one class for each card, because I've done some research and most fan made card games of Hearthstone use JSON to get the card objects. For example if the game only had 4 cards with the names: DragonMaster Vulcan Pirate Chuck Norris I'd have 4 classes, with the names respectively. Now I though this was necessary since every card would have its own behaviour,

问题 The problem : I have one class and one activity: The class do the logic and use a complex algorithms that manipulate Textview and ImageView from the activity What I'm doing : In activity : static TextView txt1, txt2, txt3, txt4; so I can use in the class : Activity.txt1 Is it something bad in Android programming ? I wanted to learn best practise. So if you have a better method I would take it. Thanks 回答1: I can't see any reason you'd ever want to do that. Static variables are shared between

问题 My problem is that I have a very slow update query on a table with 14 million rows. I tried different things to tune my server which brought good performance but not for update queries. I have two tables: T1 with 4 columns and 3 indexes on it (530 rows) T2 with 15 columns and 3 indexes on it (14 millions rows) I want to update the field vid (type integer) in T2 by the same value of vid in T1 by joining the two tables on a text field stxt. Here is my query and its output: explain analyse