Bug #9836
EHCI appears to be causing a huge interrupt storm on my ivybridge system
Status:
New
Priority:
Normal
Assignee:
-
Category:
-
Start date:
2018-09-12
Due date:
% Done:
0%
Estimated time:
Difficulty:
Medium
Tags:
needs-triage
Description
I noticed one particular core was 40% on kernel, 60% idle. Using mpstat revealed that it's getting 100's of thousands of interrupts per second:
adam@sqlbox:/home/adam$ mpstat 1 CPU minf mjf xcal intr ithr csw icsw migr smtx srw syscl usr sys wt idl 0 63 0 14 195920 195677 255 3 14 16 0 290 1 41 0 59 1 80 0 5 145 19 200 3 16 22 0 314 0 0 0 99 2 82 0 54 164 67 193 3 15 22 0 299 0 0 0 99 3 64 0 3 139 36 172 3 15 23 0 219 0 0 0 99 CPU minf mjf xcal intr ithr csw icsw migr smtx srw syscl usr sys wt idl 0 4 0 12 198278 198066 132 0 6 3 0 284 0 40 0 60 1 0 0 13 146 34 138 0 9 1 0 20 0 0 0 100 2 0 0 15 71 8 52 0 3 1 0 41 0 0 0 100 3 0 0 0 61 9 44 0 2 0 0 6 0 0 0 100 CPU minf mjf xcal intr ithr csw icsw migr smtx srw syscl usr sys wt idl 0 2 0 12 198304 198089 134 1 5 5 0 283 0 40 0 60 1 0 0 15 147 26 118 0 2 2 0 21 0 0 0 100 2 0 0 3 94 12 69 0 3 1 0 53 0 0 0 100 3 0 0 18 53 8 44 1 3 0 0 6 0 1 0 99 ^C
Narrowed this down with a modified dtrace script to show aggregations of interrupts based on device name:
adam@sqlbox:/home/adam$ cat intby.d
#!/usr/sbin/dtrace -s
/*
* inttimes.d - print interrupt on-cpu time.
* Written using DTrace (Solaris 10 3/05)
*
* $Id: inttimes.d 3 2007-08-01 10:50:08Z brendan $
*
* USAGE: inttimes.d # wait several seconds, then hit Ctrl-C
*
* FIELDS:
* DEVICE instance name of device driver
* TIME (ns) sum of time spent servicing interrupt (ns)
*
* BASED ON: /usr/demo/dtrace/intr.d
*
* SEE ALSO:
* DTrace Guide "sdt Provider" chapter (docs.sun.com)
* intrstat(1M)
*
* PORTIONS: Copyright (c) 2005 Brendan Gregg.
*
*
* 28-Jun-2005 Brendan Gregg Created this.
* 20-Apr-2006 " " Last update.
*/
#pragma D option quiet
dtrace:::BEGIN
{
printf("Tracing... Hit Ctrl-C to end.\n");
}
sdt:::interrupt-complete
/arg0 != 0/
{
this->devi = (struct dev_info *)arg0;
/* this checks the pointer is valid, */
self->name = this->devi != 0 ?
stringof(`devnamesp[this->devi->devi_major].dn_name) : "?";
this->inst = this->devi != 0 ? this->devi->devi_instance : 0;
@num[self->name, this->inst] = count();
self->name = 0;
}
dtrace:::END
{
printf("%11s %16s\n", "DEVICE", "Count");
printa("%10s%-3d %@16d\n", @num);
}
The out revealed ehci is the culprit:
adam@sqlbox:/home/adam$ sudo ./intby.d
Password:
Tracing... Hit Ctrl-C to end.
^C
DEVICE Count
ehci1 2
e1000g1 9
mpt_sas0 110
ehci0 292199
Please let me know if there's anything I should try in terms of bios settings or system configuration.
History
Updated by Adam Stylinski about 1 year ago
Updated by I should also add uname output:
adam@sqlbox:/home/adam$ uname -a
SunOS sqlbox 5.11 illumos-2eeda98682 i86pc i386 i86pc
Updated by Adam Stylinski about 1 year ago
As it turns out, one boot environment prior does not suffer from this issue:
adam@sqlbox:/home/adam$ sudo intrstat
Password:
device | cpu0 %tim cpu1 %tim cpu2 %tim cpu3 %tim
-------------+------------------------------------------------------------
e1000g#1 | 0 0.0 0 0.0 3 0.0 0 0.0
ehci#0 | 0 0.0 0 0.0 0 0.0 0 0.0
ehci#1 | 0 0.0 0 0.0 0 0.0 0 0.0
device | cpu0 %tim cpu1 %tim cpu2 %tim cpu3 %tim
-------------+------------------------------------------------------------
e1000g#1 | 0 0.0 0 0.0 3 0.0 0 0.0
ehci#0 | 1 0.0 0 0.0 0 0.0 0 0.0
ehci#1 | 0 0.0 1 0.0 0 0.0 0 0.0
device | cpu0 %tim cpu1 %tim cpu2 %tim cpu3 %tim
-------------+------------------------------------------------------------
e1000g#1 | 0 0.0 0 0.0 1 0.0 0 0.0
ehci#0 | 0 0.0 0 0.0 0 0.0 0 0.0
ehci#1 | 0 0.0 0 0.0 0 0.0 0 0.0
device | cpu0 %tim cpu1 %tim cpu2 %tim cpu3 %tim
-------------+------------------------------------------------------------
e1000g#1 | 0 0.0 0 0.0 2 0.0 0 0.0
ehci#0 | 1 0.0 0 0.0 0 0.0 0 0.0
ehci#1 | 0 0.0 1 0.0 0 0.0 0 0.0
device | cpu0 %tim cpu1 %tim cpu2 %tim cpu3 %tim
-------------+------------------------------------------------------------
e1000g#1 | 0 0.0 0 0.0 1 0.0 0 0.0
ehci#0 | 0 0.0 0 0.0 0 0.0 0 0.0
ehci#1 | 0 0.0 0 0.0 0 0.0 0 0.0
mpt_sas#0 | 0 0.0 0 0.0 0 0.0 132 0.1
device | cpu0 %tim cpu1 %tim cpu2 %tim cpu3 %tim
-------------+------------------------------------------------------------
e1000g#1 | 0 0.0 0 0.0 3 0.0 0 0.0
ehci#0 | 1 0.0 0 0.0 0 0.0 0 0.0
ehci#1 | 0 0.0 1 0.0 0 0.0 0 0.0
mpt_sas#0 | 0 0.0 0 0.0 0 0.0 0 0.0
device | cpu0 %tim cpu1 %tim cpu2 %tim cpu3 %tim
-------------+------------------------------------------------------------
e1000g#1 | 0 0.0 0 0.0 2 0.0 0 0.0
ehci#0 | 1 0.0 0 0.0 0 0.0 0 0.0
ehci#1 | 0 0.0 1 0.0 0 0.0 0 0.0
mpt_sas#0 | 0 0.0 0 0.0 0 0.0 0 0.0
adam@sqlbox:/home/adam$ uname -a
SunOS sqlbox 5.11 illumos-6640c13bea i86pc i386 i86pc
Updated by Adam Stylinski about 1 year ago
Looking between those two revisions I only see two that could possibly do something like this: one that modifies an order for an atomic look during early CPU initialization, and the other more likely: a microcode update.
Updated by Adam Stylinski 12 months ago
Just did another pkg image-update, the interrupt storm appears to be gone in illumos-e6ae04828f. Not sure if that helps any.