"hwclock -w" takes 24 seconds
Steve Bennett
steveb at workware.net.au
Wed Apr 14 06:01:08 UTC 2010
On 13/04/2010, at 11:09 AM, Rob Landley wrote:
> On Tuesday 13 April 2010 10:08:56 Kim B. Heino wrote:
>> BusyBox 1.16.1 on a small armv4tl system:
>>
>> $ time hwclock -w
>> real 0m 24.34s
>> user 0m 0.00s
>> sys 0m 0.00s
>>
>> $ time hwclock -w
>> real 0m 24.07s
>> user 0m 0.01s
>> sys 0m 0.00s
>>
>> $ time hwclock -w
>> real 0m 24.20s
>> user 0m 0.00s
>> sys 0m 0.00s
>>
>> rem_usec seems to be about 996600 after every iteration. Changing sync
>> resolution from 1ms to 5ms helps, but there has to be better solution.
>> Denys?
>
> I can confirm this on my armv4tl system image:
>
> wget http://impactlinux/com/fwl/downloads/binaries/system-image-armv4tl.tar.bz2
> tar xvjf system-image-armv4tl.tar.bz2
> cd system-image-armv4tl
> ./run-emulator.sh
>
> wait through the boot messages...
>
> (armv4tl) /home # time hwclock -w
> real 0m 24.98s
> user 0m 0.01s
> sys 0m 0.01s
>
> This assumes you have qemu 0.12.x installed.
>
> Rob
>
> P.S: As expected, application emulation is useless here:
>
> $ qemu-arm ./hwclock
> Unsupported ioctl: cmd=0xffffffff80247009
> hwclock: RTC_RD_TIME: Function not implemented
Interesting.
BusyBox v1.17.0.git
armv5teb
~ # strace hwclock -w
... blah blah ...
open("/etc/adjtime", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/dev/rtc", O_WRONLY) = -1 ENOENT (No such file or directory)
open("/dev/rtc0", O_WRONLY) = 3
gettimeofday({1271224598, 269609}, NULL) = 0
open("/etc/config/TZ", O_RDONLY) = 4
read(4, "EST-10\n", 68) = 7
read(4, "", 61) = 0
close(4) = 0
... lots of these ...
open("/etc/config/TZ", O_RDONLY) = 4
read(4, "EST-10\n", 68) = 7
read(4, "", 61) = 0
close(4) = 0
gettimeofday({1271224622, 14271}, NULL) = 0
nanosleep({0, 984729000}, NULL) = 0
gettimeofday({1271224623, 8166}, NULL) = 0
open("/etc/config/TZ", O_RDONLY) = 4
read(4, "EST-10\n", 68) = 7
read(4, "", 61) = 0
close(4) = 0
gettimeofday({1271224623, 14276}, NULL) = 0
ioctl(3, RTC_SET_TIME, {tm_sec=3, tm_min=57, tm_hour=15, tm_mday=14, tm_mon=3, tm_year=110, ...}) = 0
exit(0) = ?
Cheers,
Steve
--
µWeb: Embedded Web Framework - http://uweb.workware.net.au/
More information about the busybox
mailing list