Folks,
Me and Nick have been back and forth with the IFC6410, using Linaro's
utopic Ubuntu + 3.17 kernel, and I can now declare it stable enough to
run toolchain tests, maybe not yet builds.
The reason is that the kernel, although stable, is only just because
it throttles speed to a minimum. So, the core runs at 920MHz and the
memory bus is at its minimum frequency. Nick gathers we could speed it
up by a factor of 30% and 40% respectively while remaining on the
safety zone.
However, that would still be not enough. Currently, the boards build
LLVM in 7hs, when a Panda does it in 5h, a Chromebook does in 3.5hs
and a Chrome2 in 2hs. Improving it by 85% would get us just under 4hs,
which is still worse than a Chromebook. If we increase the CPU clock
to 1.5GHz per core, we may get it fast enough (but still slower than
the Chrome2), to be useful.
Their form-factor are better for rack-usage (remote serial, remote
reboot, small footprint), so even being slower than Chrome 2s, they'll
be faster than Chrome 1s and much more rack-friendly. That, of course,
assuming they remain stable at 1.5GHz. Heating will be an issue, but
we now have a decent server room and we can buy rack-mounted fans for
them, if we need it.
In a nutshell, I won't give up on them just yet, but I won't speed up
replacing the other boards with them either. We may have to wait a few
more releases to be sure, but I'm not expecting anything going in
production before February.
cheers,
--renato
PS: Nick, if you want to increase the clock speeds now just to see
what happens, I'm game.
Hi,
The latest toolchain on the following page appears to be broken.
http://www.linaro.org/projects/armv8/
Looking around one comes across the following path.
http://releases.linaro.org/latest/components/toolchain/.binaries
However the tarballs there yield: "You do not have permission to access this
file."
Thanks,
Chris
--
Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
== Progress ==
QEMU kernel debugging setup [5/10] [TCWG-568]
-- Setup arm Linux kernel debugging to debug watchpoints
GDB with cygwin build/testing process [2/10]
-- Figured out GDB build and test procedure on cygwin.
Miscellaneous [3/10]
-- Meetings, Emails etc
-- Hong Kong visa application: re-submission of application.
== Plan ==
QEMU kernel debugging setup [TCWG-568]
-- Try to figure out kernel debugging help for ptrace debug
GDB with cygwin build/testing process
-- Document cygwin gdb work flow
-- Buid arm-remote gdb on cygwin
-- Identify gdb-remote issues on a cygwin host if any
== This week ==
* GCC modularization project
- Fixed df.h flattening patch to build on all targets in config-list.mk
- Flattening expr.h patch in progress.
== Next week ==
- complete expr.h patch
- Submit df.h flattening patch to gcc-patches for review
- Test cfgloop.h flattening patch on all targets with ISL enabledin
config-list.mk and submit to gcc-patches for review.
Holiday [6/10]
Misc [3/10]
* Mail backlog
* Moved all current AArch64 work off 'my' Juno, as ARM needed it back
* A little bit of a look at another possible memcpy performance issue
libm exercising - TCWG-558 [1/10]
* Reduced 'needless calls to pow' to a simple test case
** Found that this is actually an all-targets thing (at least AArch32,
AArch64, x86)
* Looked through benchfft output
** Looks like only one implementation calls libm much
** This is probably just bad code, but could do with a comparison run
on non-AArch64 to be sure
=Plan=
Switch to TCWG Junos
Think about where to go next with libm exercising
Complete 'same network' workaround, test benchmark repeatability
Port benchmarking scripts to ABE repo
Get storage/automation started, if Rob has time
=Absences=
On holiday Monday 22nd Dec to Friday 2nd Jan
== Progress ==
Bug#403/#418/PR63870 [7/10]
. Prepared patches for vldN_lane/vstN_lane
. reviewed related patches on list
. code changes are ready, but reveal errors in the testsuite
Misc [3/10]
. mailing llists
. meetings
. some help with lab config with Renato
= Progress ==
* TSAN support for Aarch64 (6/10)
* Emails, linaro/AMD status meetings. (4/10)
1-1 with maxim, Christophe.
== Plan ==
* TSAN support for Aarch64.
* Fix Linaro Bug 863
== This week ==
* GCC Modularization Project (9/10)
- Flattening header files
- tree-core.h, and tree.h, c-common.h
- Completed
- Bootstrap successful on x86
- Testing in progress on all platforms listed in config-list.mk
- Reviewed and tested patches from Prathamesh
* Misc (1/10)
- Conference calls
== Next week ==
- Submit tree.h and related patches for review