How to speed-up the boot?

[jgrulich]

Hi All,
Hence the TC7 boot slower than TC6 I'm looking for some working way how to do it much, much faster. I've remastered the filesystem to have only one FAT partition without ext4. Than I've tried to remove the overlays, but it's even slower because than it tries to load all the modules, even not needed and install extensions from non-existing ext4 partition. I've used turbo with 900MHz for boot process, but still it takes 18,5 sec. to finalize the boot, means to the LAN becomes connected.

[Rich]

Hi jgrulich
If you add the boot code:

Code: [Select]

printk.time=1You will have timing information in  dmesg  which will tell you where time is being spent. The  syslog  boot code may
also prove useful. The results of that can be found in  /var/log/messages.

[jgrulich]

I know about this investigation, but the major time it takes before the first text line with TC version appears. Than it is quite fast. Means that I've asked if someone knows the way how to speed the initial time when the system is extracted into the ram and is initiated.

[curaga]

The bootloader is slow? You can only use faster media, or load less data (smaller kernel, smaller initrd).

[jgrulich]

Yes, the bootloader is slow. It takes 8 sec to get the first text line and than 10.2 sec to load whole system. I've removed all really not necessary and mandatory files from SD card, but still the same, 8 sec to start Linux. Don't know what to test to reduce this time.

[andyj]

I have noticed that when I look at the end of my Xorg logs that the last entries are at 8.5 seconds for :1 and 9.1 seconds for :0, but clock time from power on is 23 seconds. It sure does seem to take a long time to start the boot process after power on. Other than a watch, is there a reliable way to measure the POST time? How much difference does the SD card speed help?

[bmarkus]

Yes, the bootloader is slow. It takes 8 sec to get the first text line and than 10.2 sec to load whole system. I've removed all really not necessary and mandatory files from SD card, but still the same, 8 sec to start Linux. Don't know what to test to reduce this time.

Removing unneeded files has no influence. During the first 6-8s hardware is initialized. GPU reads bootloader, loads firmware for CPU, turns on RAM, starts USB and other peripheral units, etc. It is out of your control. Only thing you can do is to disable I2C, I2S in config.txt if you do need them to save 1.5s

For details see http://raspberrypi.stackexchange.com/questions/10442/what-is-the-boot-sequence

[patrikg]

Have seen on some linux systems that have some tcp/ip functions being slow, and delayed
because of no response in the dns back resolving in the "in-addr.arpa" zone.
And also in the forward zone.

The dns resolving in the systems being delayed by some timeouts by no response.

So if you having some servers in your linux system with fqdn, you can add these in to the hosts file, so the server don't need to ask the dns server.. and so on.