fgetss Freezing When Handling Large Files? Here Are Some Tips to Optimize Performance

gitbox 2025-09-29

<span><span><span class="hljs-meta"><?php</span></span>
</span><span><span class="hljs-comment">// This is a PHP code example unrelated to the article content</span></span>
</span><span><span class="hljs-keyword">echo</span></span> <span><span class="hljs-string">"Welcome to this article!<br>"</span></span>;
</span><span><span class="hljs-variable">$time_start</span></span> = <span><span class="hljs-title function_ invoke__">microtime</span></span>(<span><span class="hljs-literal">true</span></span>);
</span><span><span class="hljs-meta">?></span></span>
<hr>
</span><span><span class="hljs-meta"><?php</span></span>
</span><span><span class="hljs-comment">// Article starts</span></span>
</span><span><span class="hljs-keyword">echo</span></span> <span><span class="hljs-string">"<h1>fgetss Freezing When Handling Large Files? Here Are Some Tips to Optimize Performance</h1>"</span></span>;
</span><span><span class="hljs-comment">// Introduction</span></span>
</span><span><span class="hljs-keyword">echo</span></span> <span><span class="hljs-string">"<p>In PHP development, the fgetss function is commonly used to read file content line by line while stripping HTML tags. However, when handling large files, many developers experience noticeable freezing. This article analyzes the reasons for the slowdown and offers several methods to optimize performance.</p>"</span></span>;
</span><span><span class="hljs-comment">// 1. Understanding How fgetss Works</span></span>
</span><span><span class="hljs-keyword">echo</span></span> <span><span class="hljs-string">"<h2>1. Understanding How fgetss Works</h2>"</span></span>;
</span><span><span class="hljs-keyword">echo</span></span> <span><span class="hljs-string">"<p>The core of fgetss is reading the file line by line while removing HTML and PHP tags. For large files, each fgetss call requires string parsing and tag filtering, which introduces considerable performance overhead.</p>"</span></span>;
</span><span><span class="hljs-comment">// 2. Reasons for Slowdown with Large Files</span></span>
</span><span><span class="hljs-keyword">echo</span></span> <span><span class="hljs-string">"<h2>2. Reasons for Slowdown with Large Files</h2>"</span></span>;
</span><span><span class="hljs-keyword">echo</span></span> <span><span class="hljs-string">"<ul>
<li><strong>File too large:</strong> Reading the entire file at once consumes a lot of memory.</li>
<li><strong>Frequent I/O operations:</strong> Each fgetss call accesses the hard drive, and I/O is a performance bottleneck.</li>
<li><strong>Tag parsing overhead:</strong> fgetss parses and removes HTML tags, which is time-consuming for large text.</li>
</ul>"</span></span>;
</span><span><span class="hljs-comment">// 3. Optimization Methods</span></span>
</span><span><span class="hljs-keyword">echo</span></span> <span><span class="hljs-string">"<h2>3. Optimization Methods</h2>"</span></span>;
</span><span><span class="hljs-comment">// Method 1: Replace fgetss with fgets + strip_tags</span></span>
</span><span><span class="hljs-keyword">echo</span></span> <span><span class="hljs-string">"<h3>1. Use <code>fgets

"; // Method 3: Read file in chunks echo "

3. Read File in Chunks

"; echo "

For extremely large files, read fixed-size byte chunks at a time to reduce I/O operations:

"; echo "

\$handle = fopen('largefile.txt', 'r');
\$chunkSize = 16384;
while (!feof(\$handle)) {
    \$chunk = fread(\$handle, \$chunkSize);
    \$cleanChunk = strip_tags(\$chunk);
    // Process \$cleanChunk
}
fclose(\$handle);

"; // Method 4: Use generators for memory efficiency echo "

4. Use Generators for Memory Efficiency

"; echo "

Generators allow processing line by line without loading the entire file at once:

"; echo "

function readFileLines(\$file) {
    \$handle = fopen(\$file, 'r');
    if (!\$handle) return;
    while (!feof(\$handle)) {
        yield strip_tags(fgets(\$handle));
    }
    fclose(\$handle);
}
<p>foreach (readFileLines('largefile.txt') as $line) {<br>
// Process $line<br>
}<br>

";
// Conclusion
echo "

Conclusion

";
echo "

fgetss may indeed freeze when handling large files due to line-by-line reading and tag parsing performance bottlenecks. Using fgets+strip_tags, increasing the buffer size, reading in chunks, or leveraging generators can significantly improve performance while reducing memory usage. Choose the method that best fits your scenario to handle large files efficiently.

";
?>

fgetss