32

How long does the RasPi take to boot when using the standard Debian distribution on a typical SD card? Are we talking less than a second? A couple of seconds? 10 seconds? 100 seconds?

This isn't too important for most users and applications, but could be important for embedded solutions which are not permanently switched on.

darryn.ten
  • 1,486
  • 2
  • 14
  • 18
winwaed
  • 1,459
  • 2
  • 15
  • 25
  • I don't think there is such a thing as a "standard Debian SD card" because cards vary so much. Maybe this would be easier to answer if the foundation started selling preloaded cards (and only if they used the same model consistently.) – finnw Jun 14 '12 at 21:28
  • 1
    I'm one of those awaiting their Raspis - I was under the impression they were intending to sell them; and that there is a standard Debian distribution. I'll reword things a little... – winwaed Jun 14 '12 at 21:35
  • 2
    I think it's a perfectly valid question. A simple benchmark might be "dd this debian image to an SD card, boot 3 times and time the fastest one until you get to the logon prompt, and publish your time along with the manufacturer and class of device" – popey Jun 15 '12 at 09:16
  • 1
    Help us never-before-seen-a-raspberry-pi-boot folks struggling with hardware issues. How long does it take for anything at all to show up on the display? And I assume we're talking about a terminal login prompt, not a graphical screen prompt (since I've seen boot-to-gui debian distro options out there also)? – nealmcb Jan 22 '15 at 01:50

6 Answers6

23

This is completely dependant on the Class of SD card you are using.

A Class 4 card, which is the minimum recommended has an average read/write speed of 4 MB/sec.

If you spend a little extra and buy a Class 10 card, you should find that the boot time is approximately 25% of the Class 4, as it should read at 10MB/sec.

Using finnw's estimate that 24 seconds pass while using a Class 6 we can guess this could be reduced to 14.4 seconds with a Class 10 device.

Classes 2-10 will give you boot times something like this:

enter image description here

Update:

With the release of new hard float distributions boot time has been significantly reduced. In addition, Arch Arm Linux is now using systemd instead of init which starts processes in parallel and is considered to be much faster. As a result my Class 10 SD card now boots Arch to a login prompt in about 6-7 seconds.

Jivings
  • 22,538
  • 11
  • 90
  • 139
  • 3
    It'd be awesome if people would post their boot times & SD card class - we could see how accurate your chart is – Alex L Jun 15 '12 at 15:35
  • @Alex: I'm just flashing a Class 10. So I'll be able to see what the performance increase is like from my Class 2. I'm expecting a big difference :D – Jivings Jun 16 '12 at 15:16
  • 1
    @Alex Confirmed, Class 10 card takes about 15 seconds to boot Arch. – Jivings Jun 17 '12 at 08:38
  • 2
    I'm going to mark this as the answer, as it looks like there's a wide range of possibilities and this gives the "Grand Unified Theory" as it were. I would echo @Alex's comment, and I'll Up vote each new answer as it comes in. This should then be a useful set of answers for the future. Moderators could lock the question in a few months to avoid "Me Too" answers. – winwaed Jun 18 '12 at 13:09
  • @winwaed: Good idea. – Jivings Jun 18 '12 at 13:35
  • The SD class does not tell everything, since it is for sequential access. For an OS small random reads and writes are more important. Random writes can be substantially slower than sequential ones. More details in my answer here – Frepa Oct 23 '12 at 20:52
  • Unless you have additional references, I think you have misinterpreted what SD classes are about: https://www.sdcard.org/developers/overview/speed_class/ (from Patrick's answer on that new question). Note: "Speed Class designates minimum writing* performance"* -> emphasis on "minimum" and "writing". I and numbers of other people have reported read speeds that max out the pi (~20 MB/s) with class 4 cards. In fact, I think you would be hard pressed to find anyone with a limit as low as what you've claimed here (4 MB/s). – goldilocks Jan 14 '16 at 18:07
  • @goldilocks Yep, think of this as more of the slowest potential boot time based on the class of the card. – Jivings Jan 15 '16 at 09:54
  • Yes -- your graph seems based on the presumption that SD class is based on absolute read speed, whereas Patrick Cook and that reference say otherwise. One or the other of you is wrong, I think it's you, because as indicated in the other question, I've tested a class 4 card at 20 MB/s read and if you look at the average reported on the elinux page, it is probably > 10 MB/s. I don't think the class indicates anything about read speed at all. I.e., your graph is bogus :( – goldilocks Jan 15 '16 at 09:54
  • @goldilocks Sorry I re-read your comment and deleted my original one. – Jivings Jan 15 '16 at 09:55
17

I timed it on my Pi, and it took 24 seconds from powerup to login prompt.

This is with a Transcend Class 6 4GB SD card loaded with Debian Squeeze.

This is the card that is recommended by RS for use with the RasPi, so this may qualify as "typical" as many users will probably have this type of card.

finnw
  • 5,790
  • 3
  • 32
  • 42
  • So there's a good chance it will be the card I end up on - I'm on RS's US division's waiting list; but haven't paid much attention to cases, card types, etc. until I have a confirmed order... – winwaed Jun 18 '12 at 13:11
7

For better boot times, update the firmware (with rpi-update), install the system with hard-floats and keep it updated.

Older firmware are usually slower, hard-floats increase a lot the system speed, every day there are more optimization for arm, specially for rpi

higuita
  • 684
  • 5
  • 6
6

Patriot class 10 32Gb with nothing connected but the hdmi took 30s from power up to login prompt

David Sykes
  • 1,435
  • 3
  • 19
  • 28
6

My Kingston 4gb class 4 loaded with Debian Squeeze took 40 seconds from power up to login prompt

David Sykes
  • 1,435
  • 3
  • 19
  • 28
4

Transcend 32GB class 10 needs 30 seconds. I don't think that older and newer images boot for the same time, so results should mention image version. Mine was 2012-10-28-wheezy-raspbian.zip.

avra
  • 1,273
  • 8
  • 9