linux startup time optimization

[1182614726]

Dear all,

my bsp is 4.1.15-2.1.0 imx6dlsabresd, now i want to reduce the time of linux system booting.now when the rootfs run, and after the log "random: udevd urandom read with 20 bits of entropy available", it stops for 2 seconds, and then print the next log "INIT: Entering runlevel: 5", i don't want to wait for so long, could you help me,thank you very much.

my board is imx

[3.320321 0.002744] Freeing unused kernel memory: 416K (80a0e000 - 80a76000)
[3.403282 0.082961] INIT: version 2.88 booting
[3.741542 0.338260] Starting udev
[4.026929 0.285387] udevd[124]: starting version 3.1.5
[4.047488 0.020559] random: udevd urandom read with 20 bits of entropy available
[6.304459 2.256971] INIT: Entering runlevel: 5
[6.421424 0.116965] Configuring network interfaces... fec 2188000.ethernet eth0: Freescale FEC PHY driver [Atheros 8035 ethernet] (mii_bus:phy_addr=2188000.ethernet:04, irq=-1)
[6.613556 0.192132] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready
[6.661879 0.048323] done.
[6.718808 0.056929] Starting system message bus: dbus.
[6.793821 0.075013] Starting Connection Manager
[7.090535 0.296714]  * Starting Avahi mDNS/DNS-SD Daemon: avahi-daemon   [ ok ]
[7.326768 0.017981] Starting crond: OK
[7.357443 0.030675] Running local boot scripts (/etc/rc.local).
[7.428010 0.070567] umount: /mnt/.psplash: not mounted
[7.551353 0.123343]
[7.551375 0.000022] Freescale i.MX Release Distro 4.1.15-2.1.0 imx6dlsabresd /dev/ttymxc1

[Sasamy]

Hi qiang xie,

the problem of slow initialization of the random number generator is solved in more recent kernels

https://lwn.net/Articles/691071/

You can try backport from kernel 4.9 which we use on our custom kernel 4.1.15

https://yadi.sk/d/Z25dFw_b3TMu4D

Alexander

[1182614726]

Hi, Alexander Kudjashev

Thank you very much for you reply. I have apply the path https://yadi.sk/d/Z25dFw_b3TMu4D you provided, but now it seems appear a new problem like the below log "EXT3-fs error (device mmcblk3p2): ext3_free_blocks_sb: bit already cleared for block 524794", and the time haven't become shorter.

[3.301456 0.007453] Freeing unused kernel memory: 416K (80a10000 - 80a78000)
[3.381392 0.079936] INIT: version 2.88 booting
[3.720773 0.339381] Starting udev
[3.994052 0.273279] udevd[123]: starting version 3.1.5
[6.275846 2.281794] EXT3-fs error (device mmcblk3p2): ext3_free_blocks_sb: bit already cleared for block 524794
[6.316258 0.040412] FAT-fs (mmcblk3p1): Volume was not properly unmounted. Some data may be corrupt. Please run fsck.
[6.462294 0.146036] INIT: Entering runlevel: 5
[6.551962 0.089668] Configuring network interfaces... fec 2188000.ethernet eth0: Freescale FEC PHY driver [Atheros 8035 ethernet] (mii_bus:phy_addr=2188000.ethernet:04, irq=-1)
[6.748362 0.196400] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready
[6.797528 0.049166] done.
[6.855073 0.057545] Starting system message bus: dbus.
[6.928065 0.072992] Starting Connection Manager
[7.232509 0.304444] * Starting Avahi mDNS/DNS-SD Daemon: avahi-daemon
[7.321261 0.088752] EXT3-fs error (device mmcblk3p2): ext3_free_blocks_sb: bit already cleared for block 563638 [ ok ]
[7.463505 0.015046] Starting crond: OK
[7.493717 0.030212] Running local boot scripts (/etc/rc.local).
[7.563874 0.070157] umount: /mnt/.psplash: not mounted
[7.688459 0.124585]
[7.688491 0.000032] Freescale i.MX Release Distro 4.1.15-2.1.0 imx6dlsabresd /dev/ttymxc1