Memcached::getAllKeys

(PECL memcached >= 2.0.0)

Memcached::getAllKeys — Gets the keys stored on all the servers

说明

public Memcached::getAllKeys(): array|false

Memcached::getAllKeys() queries each memcache server and retrieves an array of all keys stored on them at that point in time. This is not an atomic operation, so it isn't a truly consistent snapshot of the keys at point in time. As memcache doesn't guarantee to return all keys you also cannot assume that all keys have been returned.

注意:
This method is intended for debugging purposes and should not be used at scale!

参数

此函数没有参数。

返回值

Returns the keys stored on all the servers on success 或者在失败时返回 false.

改进此页面

了解如何改进此页面 • 提交拉取请求 • 报告一个错误

＋添加备注

用户贡献的备注 4 notes

down

flaviu dot chelaru at gmail dot com ¶

7 years ago

// initiate the memcached instance
$cache = new \Memcached();
$cache->addServer('localhost', '11211');

// get all stored memcached items

$keys = $cache->getAllKeys();
$cache->getDelayed($keys);

$store = $cache->fetchAll();

// delete by regex keys

$keys = $cache->getAllKeys();
$regex = 'product_.*';
foreach($keys as $item) {
    if(preg_match('/'.$regex.'/', $item)) {
        $cache->delete($item);
    }
}

down

xiangku7890 at gmail dot com ¶

8 years ago

First I use the lastest memcached version 1.4.25, but unfortunately I found memcached::getAllkeys do not work with it, though i follow the others suggestion to disable Memcached::OPT_BINARY_PROTOCOL. So i try to use history versions, when i use memcached version 1.4.17, it works.

down

danb1974 at gmail dot com ¶

4 years ago

The right way to dump slab keys seems to be by using lru_crawler metadump instead of stats cachedump, see https://github.com/memcached/memcached/issues/405

<?php

function getAllKeys(string $host, int $port): array
{
    $sock = fsockopen($host, $port, $errno, $errstr);
    if ($sock === false) {
        throw new Exception("Error connection to server {$host} on port {$port}: ({$errno}) {$errstr}");
    }

    if (fwrite($sock, "stats items\n") === false) {
        throw new Exception("Error writing to socket");
    }

    $slabCounts = [];
    while (($line = fgets($sock)) !== false) {
        $line = trim($line);
        if ($line === 'END') {
            break;
        }

        // STAT items:8:number 3
        if (preg_match('!^STAT items:(\d+):number (\d+)$!', $line, $matches)) {
            $slabCounts[$matches[1]] = (int)$matches[2];
        }
    }

    foreach ($slabCounts as $slabNr => $slabCount) {
        if (fwrite($sock, "lru_crawler metadump {$slabNr}\n") === false) {
            throw new Exception('Error writing to socket');
        }

        $count = 0;
        while (($line = fgets($sock)) !== false) {
            $line = trim($line);
            if ($line === 'END') {
                break;
            }

            // key=foobar exp=1596440293 la=1596439293 cas=8492 fetch=no cls=24 size=14908
            if (preg_match('!^key=(\S+)!', $line, $matches)) {
                $allKeys[] = $matches[1];
                $count++;
            }
        }

//        if ($count !== $slabCount) {
//            throw new Exception("Surprise, got {$count} keys instead of {$slabCount} keys");
//        }
    }

    if (fclose($sock) === false) {
        throw new Exception('Error closing socket');
    }
    
    return $allKeys;
}

down

harold at snel dot me ¶

5 years ago

/**
 * Get all memcached keys. Special function because getAllKeys() is broken since memcached 1.4.23. Should only be needed on php 5.6
 *
 * cleaned up version of code found on Stackoverflow.com by Maduka Jayalath
 *
 * @return array|int - all retrieved keys (or negative number on error)
 */
public function getMemcachedKeys($host = '127.0.0.1', $port = 11211)
{
    $mem = @fsockopen($host, $port);
    if ($mem === false)
    {
        return -1;
    }

    // retrieve distinct slab
    $r = @fwrite($mem, 'stats items' . chr(10));
    if ($r === false)
    {
        return -2;
    }

    $slab = [];
    while (($l = @fgets($mem, 1024)) !== false)
    {
        // finished?
        $l = trim($l);
        if ($l == 'END') 
        {
            break;
        }

        $m = [];
        // <STAT items:22:evicted_nonzero 0>
        $r = preg_match('/^STAT\sitems\:(\d+)\:/', $l, $m);
        if ($r != 1) 
        {
            return -3;
        }
        $a_slab = $m[1];

        if (!array_key_exists($a_slab, $slab)) 
        {
            $slab[$a_slab] = [];
        }
    }

    reset($slab);
    foreach ($slab as $a_slab_key => &$a_slab)
    {
        $r = @fwrite($mem, 'stats cachedump ' . $a_slab_key . ' 100' . chr(10));
        if ($r === false) 
        {
            return -4;
        }

        while (($l = @fgets($mem, 1024)) !== false)
        {
            // finished?
            $l = trim($l);
            if ($l == 'END') 
            {
                break;
            }

            $m = [];
            // ITEM 42 [118 b; 1354717302 s]
            $r = preg_match('/^ITEM\s([^\s]+)\s/', $l, $m);
            if ($r != 1) 
            {
                return -5;
            }
            $a_key = $m[1];

            $a_slab[] = $a_key;
        }
    }

    // close the connection
    @fclose($mem);
    unset($mem);

    $keys = [];
    reset($slab);
    foreach ($slab AS &$a_slab)
    {
        reset($a_slab);
        foreach ($a_slab AS &$a_key) 
        {
            $keys[] = $a_key;
        }
    }
    unset($slab);

    return $keys;
}