Recent snapshots stop spread interrupt through multi cpu cores

For Developers
1

As title, recent snapshot just do not spread interrupts through multi cores, not like before.

root@OpenWrt:~# cat /proc/interrupts
           CPU0       CPU1       CPU2       CPU3
  8:      24744      24742      24737      24729  MIPS GIC Local   1  timer
  9:      56679          0          0          0  MIPS GIC  63  IPI call
 10:          0      88287          0          0  MIPS GIC  64  IPI call
 11:          0          0      73865          0  MIPS GIC  65  IPI call
 12:          0          0          0      51066  MIPS GIC  66  IPI call
 13:       1026          0          0          0  MIPS GIC  67  IPI resched
 14:          0       1127          0          0  MIPS GIC  68  IPI resched
 15:          0          0        929          0  MIPS GIC  69  IPI resched
 16:          0          0          0       1056  MIPS GIC  70  IPI resched
 17:          0          0          0          0  MIPS GIC  19  1e000600.gpio-bank0, 1e000600.gpio-bank1, 1e000600.gpio-bank2
 19:         12          0          0          0  MIPS GIC  33  ttyS0
 20:          0          0          0          0  MIPS GIC  29  xhci-hcd:usb1
 21:        826          0          0          0  MIPS GIC  10  1e100000.ethernet
 22:          3          0          0          0  MIPS GIC  30  mt7530
 23:          0          0          0          0    mt7530   1  mt7530-0:01
 24:          0          0          0          0    mt7530   2  mt7530-0:02
 25:          0          0          0          0    mt7530   3  mt7530-0:03
 26:          3          0          0          0    mt7530   4  mt7530-0:04
 27:          0          0          0          0  1e000600.gpio   7  keys
 28:          0          0          0          0  1e000600.gpio  18  keys
 29:      10664          0          0          0  MIPS GIC  11  mt76x2e
 30:      14198          0          0          0  MIPS GIC  31  mt76x2e
ERR:          0

BTW, my router is D-Link DIR-860L B1 act as an AP. I have to install irqbalance to get similar effect as before, which is, interrupts of the 2 wifi module handled mostly by other cpu cores other than core-0 which better be reserved for eth interrupts.

2

There was never any mechanism that I know of to spread interrupts except for irqbalance. If you installed it and it didn't tell you it was already installed, then I suspect the change in behaviour may simply be irqbalance being removed from the default set of packages for that device. It may appear again in the next release. Or you may just have to include its installation as part of your setup now.

1 Like
3

While your explaination make sense, I don't recall a config file related to irqbalance there before.