Boot Speed

[jibberegg]

Not sure if this is the correct section, but I'll go for it anyway... With the spread of SSDs connected to good SATA III controllers, boot times for PCs have fallen through the floor. Anyone know what the limiting factor is on getting this even lower? Is it still the hard drive speeds, or is something else stopping it getting down to 10 or 5 seconds?

 

[Puppies04]

You have to remember that you have 2 components to "boot" speeds, 1 is the time it takes the mobo to post and the other is the time it takes the operating system to load up. I was reading a thread on here a while back that said that a lot of mobo manufacturers put a lot of idle time into the post part of the "boot" something like this

Check for HDD, wait 50ms
Check for DVD drive, wait 50ms
check for GPU wait 50ms

You end up waiting twice as long for the system to post than the OS takes to load. Some people were saying it can take upwards or 10-15 seconds for their mobo to even reach this stage which would annoy the hell out of me if i just spend £££ on SSD's to try and reduce startup time.

 

[wuliheron]

The bios system is dated and wasn't originally designed to last this long anyway. UEFI is better suited to modern computers, faster, and considered the likely successor to bios. However, the way to really make a difference is to replace ram with nonvolatile memory and pretty much eliminate boot times altogether. Turn the computer on, and its right where you left it last.

 

[dbarton]

SSD and using Hibernation helps..

 

[Modelworks]

Hardware detection is the main issue. If you set the detection threshold time too low then hardware might not be detected, too high and the user complains it takes too long to boot. One way that can speed things up greatly would be to turn off hardware detection completely. You would need two boot modes, one for detection where you let the computer record everything installed and a second mode that uses only the saved settings and no detection.

This is really how the pc worked before the notion of plug and play. You set jumpers or dip switches and at power on the pc used those settings and didn't look for other hardware. Boot times were very quick then and only the speed of the media is what slowed it down. Look at some of the older home computers like the tandy models and commodore 64, they have instant boot to the OS because it is in ROM and the bios isn't looking for hardware at boot.

Things like EFI don't solve this issue , they merely moved the data from the motherboard to the drive to make the overall bios more universal and easier to program for, but it doesn't remove the detection issue.

The downside is users would need to understand the difference in the two modes otherwise when they pulled out memory or added a card the hardware would go unused. The current system has the pc checking and waiting for new hardware every time you power it on whether something is new or not.

 

[exdeath]

Device driver initialization and device timeouts is now the biggest factor in boot time. Most of the delay on the Windows logo are drivers following their hardware reset and init protocols where they have to wait so many xxx ms for the chip/bus/etc to reset before proceeding. Additionally, plug and play, things like USB and PCIe have timeouts when detecting and initing devices, etc. That's low level.

Then getting to desktop you have high level things like DHCP, SMB, network client, etc adding to the delays as your desktop environment loads. These delays and waits are purposely written into the software because of the nature of what it has to do, eg: wait for IP to init, then attempt to contact server, wait 5 seconds, if no contact, then log on with cached credentials, etc.

 

[jibberegg]

I didn't know/think about programmed waits; I was just thinking about SSD speed being insanely highly and it probably not being CPU limited. Insightful set of answers there! Cheers guys

 

[bwanaaa]

so would disabling plug n play in the bios speed things up? I have always read that is a no-no (but often wondered why that option is in the bios).