PHP's echo output will be very slow if there is too much content_PHP Tutorial

As an old Chinese medicine practitioner who has been around for many years, I was assigned today to solve a problem of slow front-end page display. The situation on the question page is as follows:

apache + php

Use smarty template to output content

The final output content of the page is large, 80k+

Page execution time is more than 500ms

The magic weapon xhprof was used to conduct a detailed inspection of the problematic page, and found that the bottleneck of the page turned out to be an echo statement in the template (after compilation). The string output by this echo statement was relatively large, about 50k+ bytes, and cost The time is more than 400 milliseconds, accounting for 80% of the entire page execution time. This kind of echo output is actually very common on the homepage of the site. Without database operations, the execution time should not be so long.

So I vigorously used my search skills, and finally found some clues in the echo part of the PHP manual. As early as 2003, some seniors believed that outputting large strings to the client through echo would cause performance problems on the server. According to my testing, Using print in this scenario is actually just as slow. The suggested solution is to cut the string into smaller strings for output. The display speed will be improved. The output function is as follows:

<?php
//对大字节字符串进行分割保存到数组中，然后循环输出
function echoBigChar($string,$bufferSize=8192){
	$splitString=str_split($string,$bufferSize);
	foreach($splitString as $chunk){
		echo $chunk;
	}
}

But the above prescription is not very symptomatic. The output time of the entire echobig is still around 400 milliseconds, without much improvement. Considering that it is slow to output a large amount of content to the client, I checked the apache configuration. It turned out that deflate had not been turned on for compression, so I enabled it. Use xhprof to check again, and the output time of this echo is reduced to about 5ms. From 400ms to 5ms, a configuration problem will produce an 80-fold difference, which really saves money.

This story tells us that turning on compressed output is really important.

Articles you may be interested in

• Use the PHP function memory_get_usage to obtain the current PHP memory consumption to optimize the performance of the program
• php getting content Method to list and output all pictures
• php method to get each month within a certain period of time and return an array composed of these months
• php to convert multiple consecutive spaces in a string For a space
• How to use zlib to compress output content to improve web page opening speed
• The text area textarea box adapts its height according to the input content
• What PHP programmers must know 40 code optimization items
• Javascript code summary for sharing content to major social platform websites