MacBook Pro 256GB SSD upgrade experience

April 9th 2010 • Apple, Hardware (crucial, mac, MacBook, MacBook-Pro, ssd) • 16,680 views • 16 responses

I’ve been wanting an SSD for some time and last week I caved. Armed with credit card, screwdriver and trusty MacBook Pro I fitted a sweet SSD and decided to document the experience.

Choosing a drive

There are a bewildering number of options out there. Budget, as always, dictates the combination of speed and size available.

Size

You may not need as much space as you think so even if you intend on a fresh install clean-up your current drive to get an idea of requirements.

Remembering to backup before:

1. Identify biggest culprits
   Try DaisyDisk ($19) or Disk Inventory X (free) and drill down to catch unexpected bloat in your music library, videos etc.
2. Clean up unused system junk
   Use CleanMyMac ($30) or MonoLingual (free) to clean up logs as well as redundant processor and language support.
3. Archive unused content
   Move those podcasts, TV shows, applications and games you aren’t going to use again to cheap external drives.
4. Deal with orphaned & duplicate files
   Find media in your iTunes folders missing from iTunes lists and either trash or add it back then use iTune’s Display Duplicates.

If you’re prepared to sacrifice your DVD drive then you can move your existing hard drive to the optical bay via an adaptor and purchase a smaller SSD for the OS and key performance-critical files. This saves cash and gives you more space but will cost you battery life.

Speed

SSDs are not created equal and the combination of flash and controller (on drive and in your machine) play a part in defining performance. Firmware, hardware revisions, drive size and operating system can also affect the speed so do your homework.

Anandtech have in-depth coverage of SSD’s including an SSD Bench with Tom’s providing a more general SSD Buyer’s Guide. Drives come and go quickly so keep an eye on review dates and exact model numbers as manufacturers have models with similar names with difference specifications.

My choice – lightning giant

I settled on the Crucial RealSSD C300 (CTFDDAC256MAG-1G1) because of it’s blazingly fast 256GB configuration and my storage requirements were still around 150GB.

This combination doesn’t come cheap at $699 USD. My links to the Crucial web site include my affiliate code ever optimistic I’ll get a small commission on a drive or two. (I dream that one day my blog will cover it’s own hosting charges)

Some other popular alternatives

• Intel’s X-25M G2 is well regarded and can be had for around $430 for 160GB and $210 for 80GB
• Intel’s X-25V (for value) can be had for around $120 for 40GB

Installing my SSD & Mac OS X (without a DVD drive)

The newer Unibody MacBook Pro’s hard-drives are designed to be user-replaceable and are covered in the manual.

My non-Unibody is not however those nice chaps over at iFixit have put together a hard drive replacement guide for 15” that is close enough but I have one complication. My DVD drive died which raised the question (and subsequent section)

How do I install Snow Leopard without a DVD drive?

Remote Install

Remote Install let’s you put the a DVD into a machine with a drive, run Utilities > Remote Install and follow a few steps which include holding down the alt key on the machine that doesn’t have a drive.

Unfortunately the machine wanting to boot has to be a Mac mini or a MacBook Air from 2009 or later – i.e. something Apple shipped without a DVD drive.

NetBoot

Mac’s can boot from network images however there are also obstacles here:

1. Apple’s official Netboot server is part of Mac OS X Server and that costs $499
2. The only unofficial server-less guide I could find is out of date  (nicl & NetInfo were deprecated in Leopard)

You will also need to create an image of the Mac OS X DVD to be able to install from.

USB image

Your USB device will require over 6.2GB to fit the image of Snow Leopard and need to be partitioned with GUID Partition Table which will wipe it. My 4GB memory stick was too small and I didn’t want to wipe my 1TB external drive so ended up using my 8GB Compact Flash card.

To get the Snow Leopard DVD copied to it:

1. Use a Mac that has a DVD drive and insert both the install DVD and USB storage device
2. Launch Disk Utility from the Utilities folder
3. Select the USB storage device from the list of devices and then choose the Partition tab
4. Choose 1 Partition from the Volume Scheme drop-down
5. Press Options… choose GUID Partition Table then OK
6. Press Apply to confirm you are happy to wipe away all the data on the device
7. Select the install DVD from the list of devices and then choose the Restore tab
8. Drag the install DVD from the list of devices into the Source text box
9. Drag the USB storage device from the list of devices into the Destination text box
10. Press the Restore and wait a while

When finished eject the USB device and insert it into your DVD-less Mac. Turn it on holding down alt until a boot selection screen shows and use the arrow keys and return to launch the installer from your USB device.

It may take a while for the installer screen to appear but be patient.

Press Options… from the installer to turn all off all the features you don’t need such as additional languages, printer drivers etc.

Performance over time & TRIM

A simplified primer

SSDs are fast but the flash technology suffers some limitations most importantly they can’t overwrite data without erasing it first.

In order to avoid this performance hit, and to preserve the life of the drive itself as blocks can be erased a fine number of times, SSD drives use fresh blocks for as long as they are available. Once they run out every write has to take the hit of an erase and performance can drop to traditional hard-drive speeds (or worse).

The problem arises sooner than you think because file-systems when deleting a file do not actually cause an erase but rather just de-allocate the block knowing it will get overwritten when it’s next needed so these fresh blocks decrease over time even if you drive never gets full. (Which is how file-recovery tools are able to undelete files)

This doesn’t sound too bad until you realise that when erasing a file in an operating system the file system just removes the block from it’s own list to be reused later and therefore the drive itself has no knowledge that the block can be erased until it runs out and starts honoring overwrites.

The solution

Manufacturers initially solved this problem by writing tools (for Windows) that examined the file-system structures to find out which blocks are unused so they can send ‘erase block’ commands down to the SSD drive and get your performance back – at least until you run out of blocks again.

This wasn’t a great solution so they agreed on a standard called ‘TRIM’ that lets file-systems tell the drive when blocks are no longer and can be erased in background on-demand. Support was built into Windows 7 and Linux 2.6.28 making a lot of SSD owners very happy.

Mac OS X & TRIM

Mac OS X doesn’t yet support the TRIM command although one Apple engineer confirmed they are looking at it back in October. They’re in no hurry as the SSD drives Apple ship don’t support TRIM yet.

In the mean time you might want to minimize unnecessary writes:

1. Don’t use Finder’s Secure Empty Trash or the srm command line tool – the overwriting they did on magnetic drives doesn’t overwrite on SSD but steals up to 35x the blocks of the original!
2. Keep large churning files on external drives (e.g. video processing)
3. Don’t let your laptop run out of power as it copies the RAM to disk each time (2-8GB)
4. Prevent unnecessary disk operations such as the ‘last accessed’ attribute on files (see below)
5. Don’t keep running disk benchmarks that cause lots of writes!

Turn off last-access-time

These access times are pretty useless and indeed the iPhone also has them switched off. Create a file named noatime.plist in your /Library/LaunchDaemons path with the following contents:

<plist version="1.0">
  <dict>
    <key>Label</key>
    <string>noatime</string>
    <key>ProgramArguments</key>
    <array>
      <string>mount</string>
      <string>-vuwo</string>
      <string>noatime</string>
      <string>/</string>
    </array>
    <key>RunAtLoad</key>
    <true/>
  </dict>
</plist>

Thanks go to Ricardo Gameiro for that tip although his other Mac SSD tweaks of creating a RAM disk is questionable given the way Mac OS X manages memory and disabling the RAM copy-to-disk entirely and therefore losing data is more risky to me than running out of blocks early.

Do not

• Turn off the sudden motion sensor – SSDs ignore the park head command anyway
• Turn off HFS+ journaling – some users report odd issues and corruption

Last resort

If you do get into the situation where your write performance is suffering badly and you are prepared to spend a little time to get it back you can do the following:

1. Ensure you have a full Time Machine backup
2. Boot from a Linux Live CD containing a recent build of hdparm
3. Use hdparm to perform an ATA Secure Erase
4. Boot from your Mac OS X DVD/USB stick
5. Choose the Utilities > Restore System From Backup menu option
6. Point it at your Time Machine backup

You should also be able to do this with other full-system backup tools like SuperDuper but you’ll have to figure out the steps for yourself ;-)

Performance

I wish I had some better benchmarking tools but Xbench is all I have, sorry! It’s worth bearing in mind that the non-unibody MacBook Pro I have (MacBookPro3,1) is limited to 1.5GB/sec on the SATA bus (despite having an Intel ICH-8M SATA controller)

Xbench HD Test

My original performance figures with the original as-shipped 0001 firmware and Crucial’s updated 0002 firmware:

Thoughts

SSD is fast but given the hype I was expecting everything to be instant and it wasn’t quite there. Applications do normally launched within a single dock bounce and everything feels a lot snappier but there wasn’t the massive WOW! I was expecting – at least not yet.

There are also a few other advantages often overlooked, especially on a laptop:

• lower power consumption
• less weight, noise & heat
• greater shock, dust and magnetic resistance

Here’s a table that pulls the specs compared to the 7200RPM Travestar that was previously my main drive.

Time will tell how well the machine now deals with large Aperture libraries of RAW images and Visual Studio compilations from inside Parallels and I’ll be sure to report them here.

[)amien