• Dec 13, 2010

    Computer sleep vs hibernate

    While troubleshooting my computer today to see if I could prevent it from crashing if it went into hibernate mode (where the OS saves out the contents of RAM before sleeping to the disk and completely shuts down the system), I again came across information on how to disable hibernate. I've seen this information a number of times, but didn't really pay attention to it. Recent Mac laptops, by default, have hibernate turned on which is great if your machine loses power completely and you haven't saved your work. However, I always save my work and rarely let my machine get all the way down such that the battery is completely dead. So, hibernate simply makes it longer for my machine to sleep; with the addition of 2 more GB of RAM, it takes even longer to write out the contents of RAM.

    Basically to disable hibernate mode, you issue the following command from terminal:

    sudo pmset -a hibernatemode 0

    To re-enable hibernate mode, you do:

    sudo pmset -a hibernatemode 3

    (Information from Apple's documentation.)

     

    So with that set, my machine should goto sleep faster and no longer crash on wake (due to a firmware issue with my SSD).

  • Dec 12, 2010

    Picking smoke detectors

    Fire protection experts recommend replacing batteries in smoke detectors every year when you change your clocks for daylight savings time. So this year, I heard an ad that also recommended a carbon monoxide detector which we didn't have. I started looking at combination smoke and carbon monoxide detectors, but quickly dismissed that idea as all the reviews indicated that the combo units ate batteries like crazy (my house is older and only has 1 hard wired unit). In addition, my reading suggested that houses have both ionization and photoelectric type smoke detectors. No combo unit had carbon monoxide and the 2 types of smoke detection.

    Once I resigned myself to getting a separate carbon monoxide detector, I decided on a First Alert Carbon Monoxide Alarm. This was based on reviews by Consumer Reports, I believe. That was the easy part; I got one for upstairs and one for downstairs. Right now our son sleeps on a bed in our room, so we don't need one in his room. When he moves back into his room, I'll get one for his room.

    The second part of this equation was finding ionization and photoelectric smoke detectors. Photoelectric detection is supposed to be better for smoldering fires and ionization is better for flaming fires according to the US Fire Administration (who even knew that this agency existed?). There are a small number of units that do both, so my choices were very few. It's really surprising to me as the recommendation is to have both types. After going to Home Depot and looking at a few (after some research), I decided on the Kidde PI9000 Battery-Operated Dual Ionization and Photoelectric Sensor Smoke Alarm. I had to replace 7 smoke detectors and install another one, so this wasn't cheap.

    After I replaced all the units, I saw that most of the units were manufactured over 10 years ago. The US Fire Administration recommends replacing the entire unit every 8-10 years, so it was about time anyway to replace them.

    So far, I know that at least one of the units works as it went off last night when my wife burned some pizza and opened the oven. Luckily the units have a hush button to temporarily shut them up (much safer than yanking the battery and forgetting to put it back in).

    Why was this process so hard? Are my sights too high in trying to protect my family and my house? How many average homeowners learn so much about smoke detectors? My guess is probably quite few. I'll just add this as another topic that I have more than cursory knowledge.

    (Newer houses are required to have interconnected smoke alarms which sound all of the units when one goes off; retrofitting a house for this is not easy and there are only a few that offer wireless interconnect and none of those are both photoelectric and ionization. I did consider this for a few minutes, but quickly dismissed it.)

  • Dec 12, 2010

    Unsupported MacBook Pro RAM upgrade

    As I mentioned in my last post, I wanted to get more performance out of my 2 year old MacBook Pro. When I purchased machine, I got it installed with the maximum amount of RAM that I could, 4 GB. Newer machines support up to 8 GB of RAM and I'll definitely get 8 GB when I get a new machine. I had read reports of people putting 6 GB of RAM in my vintage machine and as RAM is one of the limiting factors in performance, I did a little investigating and everything I read said that there were no issues. Typically putting more RAM in a machine than the hardware supports leads to kernel panics and random crashes.

    I decided to give the 6 GB of RAM a try as it would let me put the 4 GB in my machine in my wife's machine (she had 2 GB) and speed up her machine a little. OWC had a 6 GB upgrade kit that wasn't too expensive (the drive has dropped $15 from when I got it a month ago. (I realize it sounds like I'm spending money like crazy on things, but my computer is a tool that I use to earn money, so getting better tools, I can do my job better.)

    The only downside to 6 GB is that there is a slight performance increase by having paired memory modules and 6 GB comes with a 2 GB and a 4 GB module. However, what I've read has shown that the increase in RAM outweighs the paired performance.

    I easily installed the RAM and so far, I haven't had a kernel panic due to the RAM (only kernel panic has been due to my machine hibernating with my new SSD). The extra RAM has been quite nice as I can run more apps at once without apps paging out to virtual memory. If you have a machine that is the same vintage as my MacBook Pro, I'd definitely recommend this RAM upgrade. It's not that expensive and has huge benefits (more RAM is always better).

     

  • Dec 12, 2010

    Review: OWC Mercury Extreme Pro SSD

    As computers are the tools that I use to earn my living, I invest in getting the best machine for my needs and replace my main machine about every 2 years. My current MacBook Pro 15", I bought in October 2008, so when Apple announced an event this past October, I was hoping for a significant update to the MacBook Pros, but instead they announced a new MacBook Air. (Apple did announce a 2.8 GHz option for the Core i7 MacBook Pros, but that wasn't enough for me.) So I decided to wait until the next upgrade which I hope will be in the first half of next year.

    What was I to do to squeak a little more performance out of my aging workhorse? While many developers have decked out Mac Pros with lots of RAM and horsepower, I prefer a laptop as it lets me work anywhere and having a main machine and a secondary machine is just a nightmare trying to find files (I've done that before). A colleague had mentioned that he had put an SSD into his development machine and seen a nice performance increase. So after a little research, I decided to get a Mercury Extreme SSD (240 GB) from OWC. Since Macs don't support TRIM, I needed a drive that wouldn't degrade performance over time leading me to the Mercury Extreme (since I purchased the drive, other drives have come onto market that apparently don't require TRIM support in the OS).

    Installation was as easy as any internal harddrive in a MacBook Pro (a few screws and presto) and copying my old drive to the SSD was very easy using SuperDuper!. I placed the old drive in my Voyager Q drive dock and waited for the copy to finish. Once the copy finished, I restarted and presto, it booted quickly and my SSD was running.

    I've been using the SSD for about 1.5 months now and it has been working well with one exception. There is a firmware bug that causes the Mac to crash if the machine goes into hibernate mode and then you try to wake it. OWC has told me that a firmware upgrade should be available soon. I've only hit this twice as my machine rarely goes into hibernate.

    Most of the speed tests I've seen on SSDs compare boot times, but I don't reboot all that often, so while the speed is nice at startup, it's kind of a pointless test for me. During everyday operation, I'm actually a little disappointed in the speed. I expected my machine to be blazingly fast after reading all the positives about SSDs. There are 3 factors that affect computer performance, processor speed, RAM, and I/O speed (hard drive/SSD is typically the limiting factor). Maybe I'm spoiled, but this upgrade was a bit expensive for the little gain I've seen (or maybe now I'm used to the faster speed and can't remember the slower speed).

    Pros

    • Decreases boot up time.
    • May have a small performance increase in overall machine operation.
    • Silent.
    • Less prone to damage causing by moving the machine (hard drive platters could get damaged if they aren't parked before moving).

    Cons

    • Expensive.
    • Performance increase may be minimal depending on how the machine is used.
    • Firmware bug crashes machine on wake from hibernate.

    Summary

    I'm not sure that adding an SSD is going to be worth it for most people. I've read lots of reviews showing the drives as amazing, but routinely show decreased boot up times which I only see rarely as I put my machine to sleep all the time instead of shut it down. SSDs are coming down in price, but still you can get a much larger 7200 RPM mechanical hard drive for a whole lot less and the 7200 RPM vs 5400 RPM that comes stock in most machines may be a better use of money (I've had a 7200 RPM drive in my machine since day one).

    When I buy my next machine, I'll definitely get an SSD in it direct from Apple as it will let me eek every last bit of performance out of the new machine. If the price of SSDs drop significantly, then replacing a mechanical drive with an SSD will become an easier decision.