SQM problem in snapshot version (cake is not usable)

[eduardo010174]

Xiaomi Mi Router 3G
OpenWrt SNAPSHOT r10551-d616b2c906 / LuCI Master (git-19.199.37722-776e6d5)

Luci only show in sqm fq_codel. But kmod cake is installed.

Fri Jul 19 18:08:55 2019 user.notice SQM: Starting SQM script: piece_of_cake.qos on eth0.2, in: 12000 Kbps, out: 875 Kbps
Fri Jul 19 18:08:55 2019 user.notice SQM: ERROR: cmd_wrapper: tc: FAILURE (2): /usr/sbin/tc qdisc replace dev TMP_IFB_4_SQM root cake
Fri Jul 19 18:08:55 2019 user.notice SQM: ERROR: cmd_wrapper: tc: LAST ERROR: RTNETLINK answers: No such file or directory
Fri Jul 19 18:08:55 2019 user.notice SQM: ERROR: QDISC cake is NOT useable.

[hnyman]

Known problem for targets using kernel 4.14 or older.
A separate cake module was removed as it has been upstreamed into Linux itself in 4.19.

So, cake works for those targets that use kernel 4.19

[bahtsiz_bedevi]

I was banging my head whole day for this after installing latest snapshot

[bahtsiz_bedevi]

What about devices still use 4.14 kernel? Does that mean there is no SQM cake for them?

[fuller]

@bahtsiz_bedevi

Does that mean there is no SQM cake for them?

no.
mostly cosmetic change

[Barrakketh]

Are you sure? The commit mentioned:

CAKE made it to kernel 4.19 and since OpenWrt now at kernel 4.19 we can
drop the out of tree cake package in base repository.

To me that seems that if you're using a target on 4.14 you won't have cake, though I suppose if you're building yourself you could probably revert those commits for the time being.

[fuller]

@Barrakketh

Are you sure? The commit mentioned:

sry, not sure.
misread question as "was cake available before this commit"

[hnyman]

@Barrakketh

To me that seems that if you're using a target on 4.14 you won't have cake, though I suppose if you're building yourself you could probably revert those commits for the time being

You are right. There is no cake for 4.14 unless you revert that commit for your own build.

[Barrakketh]

Good to know. I do have a question: are those changes going to be merged into 19.07, or are they for the next release?

Right now my router looks like it'll be on 4.14 come 19.07 (currently on 4.9, ar71xx), but in master the ath79 target is on 4.19.

[hnyman]

@Barrakketh

are those changes going to be merged into 19.07, or are they for the next release?

Right now my router looks like it'll be on 4.14 come 19.07 (currently on 4.9, ar71xx), but in master the ath79 target is on 4.19.

Likely not, so cake will stay usable for SQM in 19.07, but you might ask @ldir who did the original change in master.

At least for ipq806x, the 4.19 transition is still in research phase, so we might need to live without cake for some time (in master).

[ldir]

I submitted a PR to packages with amongst a few things an out of tree version of cake to temporarily fill the gap whilst 4.14 targets remain. https://github.com/openwrt/packages/pull/9594

I don't enjoy the 'interaction' that occurs on github PRs so I won't be getting involved with the PR at all. Feel free to take the commits, modify, drop, whatever, I don't wish to get involved with that repo.