I attempted to install memcached via MacPorts earlier today, and ran into a problem with the MD5 and SHA1 hashes.

$ sudo port install memcached
-->  Fetching memcached
--->  Attempting to fetch memcached-1.2.6.tar.gz from http://www.danga.com/memcached/dist/
--->  Verifying checksum(s) for memcached
Error: Checksum (md5) mismatch for memcached-1.2.6.tar.gz
Error: Checksum (sha1) mismatch for memcached-1.2.6.tar.gz
Error: Target org.macports.checksum returned: Unable to verify file checksums
Error: Status 1 encountered during processing.

After pulling down the file directly from the memcached web site, I discovered that tar wouldn’t extract it.

$ tar zxvf memcached-1.2.6.tar.gz

gzip: stdin: not in gzip format
tar: Child returned status 1
tar: Error exit delayed from previous errors

No matter; we’ll do it the hard way. These are the steps I followed to install memcached on my Mac. The only assumptions I’m consciously making are that you use MacPorts and git.

1. Install libevent through MacPorts:

$ sudo port install libevent

2. Clone the memcached git repository:

$ git clone http://consoleninja.net/code/memcached/memcached.git/

3. Configure memcached:

$ cd memcached
$ ./autogen.sh
$ ./configure --prefix=/usr/local --with-libevent=/opt/local

4. Make and install:

$ make
$ sudo make install

If everything went according to plan, you’re good to go. Start it up:

$ memcached -vv

That last line starts up a memcached server running on the default port 11211. The -vv option tells memcached to use its most verbose output. You should have seen output similar to the following:

slab class   1: chunk size     88 perslab 11915
slab class   2: chunk size    112 perslab  9362
slab class   3: chunk size    144 perslab  7281
slab class   4: chunk size    184 perslab  5698
slab class   5: chunk size    232 perslab  4519
slab class   6: chunk size    296 perslab  3542
slab class   7: chunk size    376 perslab  2788
slab class   8: chunk size    472 perslab  2221
slab class   9: chunk size    592 perslab  1771
slab class  10: chunk size    744 perslab  1409
slab class  11: chunk size    936 perslab  1120
slab class  12: chunk size   1176 perslab   891
slab class  13: chunk size   1472 perslab   712
slab class  14: chunk size   1840 perslab   569
slab class  15: chunk size   2304 perslab   455
slab class  16: chunk size   2880 perslab   364
slab class  17: chunk size   3600 perslab   291
slab class  18: chunk size   4504 perslab   232
slab class  19: chunk size   5632 perslab   186
slab class  20: chunk size   7040 perslab   148
slab class  21: chunk size   8800 perslab   119
slab class  22: chunk size  11000 perslab    95
slab class  23: chunk size  13752 perslab    76
slab class  24: chunk size  17192 perslab    60
slab class  25: chunk size  21496 perslab    48
slab class  26: chunk size  26872 perslab    39
slab class  27: chunk size  33592 perslab    31
slab class  28: chunk size  41992 perslab    24
slab class  29: chunk size  52496 perslab    19
slab class  30: chunk size  65624 perslab    15
slab class  31: chunk size  82032 perslab    12
slab class  32: chunk size 102544 perslab    10
slab class  33: chunk size 128184 perslab     8
slab class  34: chunk size 160232 perslab     6
slab class  35: chunk size 200296 perslab     5
slab class  36: chunk size 250376 perslab     4
slab class  37: chunk size 312976 perslab     3
slab class  38: chunk size 391224 perslab     2
slab class  39: chunk size 489032 perslab     2
<4 server listening
<5 server listening
<6 send buffer was 9216, now 7456540
<6 server listening (udp)

We can easily test that it’s working. Leave memcached running in the Terminal, and open a new tab. Then telnet in like so:

$ telnet 127.0.0.1 11211

If you see the following, you’re in:

Trying ::1...
Connected to localhost.
Escape character is '^]'.

If we switch back to memcached, we see:

<7 new client connection

In the future, you can launch memcached with the -d option for it to run as a daemon. If you’d like memcached to start up automatically, you can set up a launchd plist for the purpose. The following is a slightly modified version of this example:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>memcached</string>
    <key>ProgramArguments</key>
    <array>
        <string>/usr/local/bin/memcached</string>
        <string>-l</string>
        <string>127.0.0.1</string>
        <string>-u</string>
        <string>nobody</string>
        <string>-d</string>
        <string>-m</string>
        <string>64</string>
        <string>-p</string>
        <string>11211</string>
    </array>
    <key>RunAtLoad</key>
    <true/>
    <key>StandardOutPath</key>
    <string>/dev/null</string>
    <key>StandardErrorPath</key>
    <string>/dev/null</string>
</dict>
</plist>

This file is saved in ~/Library/LaunchAgents/memcached.plist, and will tell Leopard to launch memcached on startup. It will run as a daemon listening to 127.0.0.1 on port 11211 with a maximum memory size of 64MB. This is exactly the same as running the following command line:

$ memcached -l 127.0.0.1 -u nobody -d -m 64 -p 11211