Bug 715300

Summary:	statics for TTY devices are not available
Product:	Red Hat Enterprise Linux 5	Reporter:	Branislav Náter <bnater>
Component:	kernel-xen	Assignee:	Xen Maintainance List <xen-maint>
Status:	CLOSED NOTABUG	QA Contact:	Virtualization Bugs <virt-bugs>
Severity:	medium	Docs Contact:
Priority:	low
Version:	5.7	CC:	drjones, leiwang, pcao, qwan, xen-maint
Target Milestone:	rc
Target Release:	---
Hardware:	Unspecified
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2011-06-29 13:55:26 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Branislav Náter 2011-06-22 13:52:34 UTC

Description of problem:
It's not possible to view statistics for TTY devices using "sar -y" command. sadc is gathering data from files in /proc/tty/driver/ directory. This directory is empty on ia64 machines with xen kernel (2.6.18-238.el5xen in this case). These files exists on ia64 machine with 2.6.18-268.el5 kernel.

Version-Release number of selected component (if applicable):
sysstat-7.0.2-9.el5.ia64
2.6.18-238.el5xen

How reproducible:
always

Steps to Reproduce:
1. install sysstat, start sysstat service
2. run sar -y
  
Actual results:
message "Requested activities not available in file"

Expected results:
Actual tty statistics

Comment 1 Andrew Jones 2011-06-29 09:01:08 UTC

Which specific device(s) are you looking for? When running on xen there's a good chance the device doesn't work, and the substitute device (if there is one) may or may not implement proc handlers.

Comment 2 Branislav Náter 2011-06-29 13:40:37 UTC

I'm looking for this devices:

# cat /proc/tty/driver/serial 
serinfo:1.0 driver revision:
0: uart:16550A mmio:0xFF5E2000 irq:49 tx:0 rx:0
1: uart:16550A mmio:0x88033000 irq:55 tx:2172 rx:0
<snip>

I recently find out that "serial" file is also missing on s390x with regular kernel 2.6.18-238.9.1.el5 but I don't know if this is somehow related to this issue.

Comment 3 Andrew Jones 2011-06-29 13:55:26 UTC

That device won't show up on dom0 kernels (or any paravirt guest kernels, -xen kernels). They use the xen console instead of serial. Only HVM guests will have this device in /proc. I'm closing as not-a-bug.