Description of problem: Is it possible that blkiomon does not understand the output of blktrace when working with logical volume device? If I replace logical volume device with physical device, blkiomon prints I/O statistics as expected. Version-Release number of selected component (if applicable): blktrace-1.0.0-4.el5 How reproducible: always Steps to Reproduce: # df -l Filesystem 1K-blocks Used Available Use% Mounted on /dev/mapper/VolGroup00-LogVol00 30503744 2401924 26527320 9% / /dev/sda1 102182 9510 92672 10% /boot/efi tmpfs 990720 0 990720 0% /dev/shm # blktrace -w 30 -o physical -d /dev/sda Device: /dev/sda CPU 0: 0 events, 8 KiB data CPU 1: 0 events, 0 KiB data Total: 0 events (dropped 0), 8 KiB data # ls -l physical.blktrace.* -rw-r--r-- 1 root root 7968 May 6 10:20 physical.blktrace.0 -rw-r--r-- 1 root root 0 May 6 10:20 physical.blktrace.1 # blktrace -w 30 -o logical -d /dev/mapper/VolGroup00-LogVol00 Device: /dev/mapper/VolGroup00-LogVol00 CPU 0: 0 events, 2 KiB data CPU 1: 0 events, 0 KiB data Total: 0 events (dropped 0), 2 KiB data # ls -l logical.blktrace.* -rw-r--r-- 1 root root 1680 May 6 10:22 logical.blktrace.0 -rw-r--r-- 1 root root 0 May 6 10:22 logical.blktrace.1 [root@hp-lp1 ~]# blktrace -w 30 -o - -d /dev/mapper/VolGroup00-LogVol00 | blkiomon -I 10 -h - # echo $? 0 Actual results: blkiomon is quiet Expected results: blkiomon prints I/O statistics
This is somewhat expected, based on the original design intent: DESCRIPTION blkiomon is a block device I/O monitor. It periodically generates per device request size and request latency statistics from blktrace data. It provides histograms as well as data that can be used to calculate min, max, average and variance. For this purpose, it consumes D and C traces read from stdin. and from blkparse C and D traces are: C -- complete A previously issued request has been completed. The out- put will detail the sector and size of that request, as well as the success or failure of it. D -- issued A request that previously resided on the block layer queue or in the i/o scheduler has been sent to the driver. but the higher-level drivers never see these completions ... I'm not sure we can make this work for anything above the /dev/sd* devices. /* we need an older D trace and a younger C trace */ if (t_old->bit.action & BLK_TC_ACT(BLK_TC_ISSUE) && t_young->bit.action & BLK_TC_ACT(BLK_TC_COMPLETE)) { /* matching D and C traces - update statistics */ match++; blkiomon_account(&t_old->bit, &t_young->bit); blkiomon_free_trace(t_stored); return t; } /dev/dm-* and /dev/md* won't see those BLK_TC_COMPLETE actions...
Sorry, I should have read the man page more thoroughly.
No problem, it's not at all obvious; the manpage should probably be updated to make this more clear.
Some of the less critical bugs for blktrace didn't make it for RHEL5.4, but we can get to them in RHEL5.5. For this one we probably just need a manpage update. Thanks, -Eric
This request was evaluated by Red Hat Product Management for inclusion, but this component is not scheduled to be updated in the current Red Hat Enterprise Linux release. If you would like this request to be reviewed for the next minor release, ask your support representative to set the next rhel-x.y flag to "?".
The patch was sent to the upstream
(In reply to comment #7) > The patch was sent to the upstream Edward do you have a pointer to that upstream post? What are the plans for pulling it in to RHEL5.x (and RHEL6)?
(In reply to comment #8) > (In reply to comment #7) > > The patch was sent to the upstream > > Edward do you have a pointer to that upstream post? http://marc.info/?l=linux-btrace&m=126089936523206&w=2 > What are the plans for > pulling it in to RHEL5.x (and RHEL6)? will be pulled
sorry, this is the correct pointer: http://marc.info/?l=linux-btrace&m=126089938423231&w=2
This request was evaluated by Red Hat Product Management for inclusion in the current release of Red Hat Enterprise Linux. Because the affected component is not scheduled to be updated in the current release, Red Hat is unfortunately unable to address this request at this time. Red Hat invites you to ask your support representative to propose this request, if appropriate and relevant, in the next release of Red Hat Enterprise Linux.
This request was evaluated by Red Hat Product Management for inclusion in the current release of Red Hat Enterprise Linux. Because the affected component is not scheduled to be updated in the current release, Red Hat is unable to address this request at this time. Red Hat invites you to ask your support representative to propose this request, if appropriate, in the next release of Red Hat Enterprise Linux.
This bug/component is not included in scope for RHEL-5.11.0 which is the last RHEL5 minor release. This Bugzilla will soon be CLOSED as WONTFIX (at the end of RHEL5.11 development phase (Apr 22, 2014)). Please contact your account manager or support representative in case you need to escalate this bug.
Thank you for submitting this request for inclusion in Red Hat Enterprise Linux 5. We've carefully evaluated the request, but are unable to include it in RHEL5 stream. If the issue is critical for your business, please provide additional business justification through the appropriate support channels (https://access.redhat.com/site/support).