On 11/7/22 10:27, Xiangyu Chen wrote:
On 11/7/22 10:18, Khem Raj wrote:
CAUTION: This email comes from a non Wind River email account!
Do not click links or open attachments unless you recognize the
sender and know the content is safe.
On Sun, Nov 6, 2022 at 5:21 PM Xiangyu Chen
<[email protected]> wrote:
On 11/1/22 09:48, Xiangyu Chen wrote:
With the default jitter options aarch64 CPU-based devices typically
experience continuous
high CPU utilisation for several minutes after rngd starts.
Accoring to the rng-tools issue #150[1] and comments[2],in order to
address this,
the following configuration changes have been made, those
configurations
also can be found on Alpine Linux[3]:
- reduce the number of threads used to 1 in total, rather than 1
per core.
- reduce the buffer size from 16535 to 4133 which reduces the time
taken
to fill the buffer (and so reduces the duration of CPU load).
[1] https://github.com/nhorman/rng-tools/issues/150
[2]
https://github.com/nhorman/rng-tools/issues/150#issuecomment-953079212
[3]
https://git.alpinelinux.org/aports/tree/main/rng-tools/rngd.confd-arm
Signed-off-by: Xiangyu Chen <[email protected]>
---
Changes in V2:
*put the aarch64 specific default file in
meta/recipes-support/rng-tools/rng-tools/aarch64
Friendly ping. Is there any more concern on this?
My concern is that will it be so for all aarch64 machines ?
Please discard this thread, we also found that the rng-tools high cpu
usage not only on ARM64 but also on ARM32 platform(also include
qemuarm/qemuarm64), it's a common issue on ARM platform.
A new patch has been sent to list as below link, tested in my local
setup, thanks.
https://lists.openembedded.org/g/openembedded-core/message/173266
https://patchwork.yoctoproject.org/project/oe-core/patch/[email protected]/
Thanks,
Xiangyu
I tested two aarch64 platforms on my hand, zynqmp and raspi4, the
rng-tools behavior is the same, when service start, the jitter random
generator would load full cpu cores load. It would cause other
services take long time to start. I also checked another linux
distribution, so far, only Alpine Linux processed this issue and it
applied those configurations on all aarch64 platforms.
Thanks,
Xiangyu
Thanks,
Xiangyu
---
.../rng-tools/rng-tools/aarch64/default | 11
+++++++++++
1 file changed, 11 insertions(+)
create mode 100644
meta/recipes-support/rng-tools/rng-tools/aarch64/default
diff --git a/meta/recipes-support/rng-tools/rng-tools/aarch64/default
b/meta/recipes-support/rng-tools/rng-tools/aarch64/default
new file mode 100644
index 0000000000..5a2fbcc9ef
--- /dev/null
+++ b/meta/recipes-support/rng-tools/rng-tools/aarch64/default
@@ -0,0 +1,11 @@
+# With the default jitter options Arm CPU-based devices typically
experience
+# continuous high CPU utilisation for several minutes after rngd
starts.
+# See https://gitlab.alpinelinux.org/alpine/aports/-/issues/13035 and
+# https://github.com/nhorman/rng-tools/issues/150
+# In order to address this the following configuration changes have
been made:
+#
+# - reduce the number of threads used to 1 in total, rather than 1
per core.
+# - reduce the buffer size from 16535 to 4133 which reduces the
time taken
+# to fill the buffer (and so reduces the duration of CPU load).
+#
+EXTRA_ARGS="-r /dev/hwrng -O jitter:buffer_size:4133 -O
jitter:refill_thresh:4133 -O jitter:thread_count:1"
-=-=-=-=-=-=-=-=-=-=-=-
Links: You receive all messages sent to this group.
View/Reply Online (#173396):
https://lists.openembedded.org/g/openembedded-core/message/173396
Mute This Topic: https://lists.openembedded.org/mt/94701000/21656
Group Owner: [email protected]
Unsubscribe: https://lists.openembedded.org/g/openembedded-core/unsub
[[email protected]]
-=-=-=-=-=-=-=-=-=-=-=-
