Peter Rajnoha [Tue, 12 Jul 2016 07:52:18 +0000 (09:52 +0200)]
blkdeactivate: add -m|--mpathoption disablequeueing and use it for blk-availability systemd service and initscript
blkdeactivate -m disablequeueing causes "multipathd disablequeueing maps"
call inside blkdeactivate script before deactivating devices. This
avoids a situation where blkdeactivate may wait for paths to appear if
multipath is set to queueing and there's a stack of other devices and/or
mount points on top of such multipath device.
See also https://bugzilla.redhat.com/show_bug.cgi?id=1344381.
Reduce number of evualted pvcreate commands.
Since 0 is default value used to fill missing params,
and 0 is also 1st. value in array, it's being tested.
When logging to epoch files we would like to prevent creating too large
log files otherwise a spining command could fulfill available space
very easily and quickly.
Make the --filemap switch take no arguments and instead accept one
or more files on the command line to be mapped and placed into
groups.
This allows --filemap to be used with a glob:
# dmstats create --filemap *
rhel5.10-1.qcow2: Created new group with 87 region(s) as group ID 1564.
rhel5.10.qcow2: Created new group with 8 region(s) as group ID 1651.
rhel7.0-1.qcow2: Created new group with 11 region(s) as group ID 1659.
rhel7.0.qcow2: Created new group with 1454 region(s) as group ID 1670.
vm.img: Created new group with 2 region(s) as group ID 3124.
David Teigland [Fri, 8 Jul 2016 19:08:55 +0000 (14:08 -0500)]
lvconvert: allow splitcache on hidden/used cache pool
lvconvert --splitcache VG/CachePool_corig
Allow the split via the hidden/used cache pool for the time being,
since the new lvconvert code did intend to allow it, but was just
missing the exception in the list of hidden LVs that were allowed.
The preferred method for splitcache is to run it on the visible
cache LV, not the hidden cache pool. That may eventually become
the only method since we try to avoid running commands on
hidden LVs.
When a 'dmstats create --filemap' operation fails (e.g. during
open(2), close(2), or dm_stats_create_regions_from_fd()), use the
canonical version of the path. This avoids cryptic/confusing error
messages when symbolic links exist in the path argument given:
# dmstats create --filemap /var/lib/libvirt/images/my.img
Cannot map file: not a device-mapper device.
Could not create regions from file /var/lib/libvirt/images/my.img
Command failed
Using the canonical path the error is immediately obvious:
# dmstats create --filemap /var/lib/libvirt/images/my.img
Cannot map file: not a device-mapper device.
Could not create regions from file /boot/my.img
Command failed
Grouping is also useful in combination with --segments: creating a
group allows both individual segment data and data for the device
as a whole to be presented in the same report.
Support grouping for 'create --segments' in the same manner as for
'create --filemap'; group regions by default, applying an optional
alias specified with --alias, unless the user specifies --nogroup.
libdm: add aggregation support to dm_stats_get_histogram()
Support aggregate group and region histograms by allocating a new
histogram from the pool and populating it with a sum of the histogram
data for the areas contained in the region or group.
To avoid repeatedly summing the same histogram data, cache the pointer
in the group and regions structs for subsequent access. The aggregate
histograms are allocated from the same pool as the area histograms in
the corresponding handle and will be discarded at each list or populate
operation.
Bryn M. Reeves [Thu, 30 Jun 2016 20:48:10 +0000 (21:48 +0100)]
dmstats: add create --filemap
Add a new option to the create command to create regions that map the
extents of a file:
# dmstats create --filemap /path/to/file
/path/to/file: Created new group with 10 region(s) as group ID 0.
When performing a --filemap no device argument is required (and
supplying one results in error) since the device to bind to is implied
by the file path and is obtained directly from an fstat().
Grouping may be optionally disabled by the --nogroup switch: in this
case the command will report each region individually:
# dmstats create --nogroup --filemap /path/to/file
/path/to/file: Created new region with 1 area as region ID 0.
/path/to/file: Created new region with 1 area as region ID 1.
/path/to/file: Created new region with 1 area as region ID 2.
When grouping regions the group alias is automatically set to the
basename (as returned by dm_basename()) of the provided file.
This can be overridden to a user-defined value at the command line by
use of the --alias option.
If grouping is disabled no alias can be set.
Use of offset and subdivision options (--start, --length, --segments,
--areas, --areasize).
Setting aux_data and histograms for groups is possible but is not
currently implemented.
Bryn M. Reeves [Thu, 30 Jun 2016 20:46:43 +0000 (21:46 +0100)]
libdm: add dm_stats_create_regions_from_fd()
Add a call to create dmstats regions that correspond to the extents
present in a file descriptor open on a file in a local file system.
The file must reside on a file system type that correctly supports
physical extent location data in the FIEMAP ioctl.
Regions are optionally placed into a group with a user-defined alias.
File systems that do not support physical offsets in FIEMAP (btrfs
currently) are detected via fstatfs() - although attempting to map
a --filemap group on btrfs will fail anyway with the generic error
"Not on a device-mapper device" this is confusing; the file system
mount is on a device-mapper device, but btrfs' volume layer masks
this in the returned st_dev field since the returned logical file
extents may span multiple physical devices.
libdm: fix group resource leak in dm_stats_delete_region()
The function _stats_remove_region_id_from_group() incorecctly set
the group_id to DM_STATS_GROUP_NOT_PRESENT _before_ the call to
_stats_group_destroy(). This will cause the destroy function to
return immediately without doing anything:
Invalidating the ID in _stats_region_region_id_from_group() is
redundant anyway; it is rightly done as the last operation in
_stats_group_destroy (and it is not possible for anything to see
the old value between the two calls).
Remove the change to group_id to ensure that the alias and bitset
resources are correctly freed.
libdm: enclose dm_stats_walk_do/while() body in do..while
The call to dm_stats_walk_start() before the do statement makes
dm_stats_walk_do() behave inconsistently depending on context;
wrap them in an additional do { } while (0) so that the macro
always expands to a valid statement.
David Teigland [Wed, 6 Jul 2016 21:44:18 +0000 (16:44 -0500)]
lvconvert: allow converting type raid1 to type linear
The code could perform this conversion but ironically
did not recognize the standard command form, only the
the unpreferred "implication-based" command form.
"lvconvert --type linear VG/RaidLV" would fail, but
"lvconvert --mirrors 0 VG/RaidLV" would succeed.
David Teigland [Wed, 6 Jul 2016 21:33:25 +0000 (16:33 -0500)]
lvconvert: allow converting type mirror to type linear
The code could perform this conversion but ironically
did not recognize the standard command form, only the
the unpreferred "implication-based" command form.
"lvconvert --type linear VG/MirrorLV" would fail, but
"lvconvert --mirrors 0 VG/MirrorLV" would succeed.
libdm: check for empty aux_data in _parse_aux_data_group()
If after extracting stats arguments and group tags nothing remains
of aux_data but '-' set the region->aux_data field to the empty
string to match behaviour for non-grouped regions.
libdm: do not permit grouping regions with histograms
Although not harmful do not allow a group containing regions with
histograms since it is not currently possible to present histogram
data aggregated for the group.
libdm: check non-zero io count in _average_{rd,wr}_wait_time (Coverity)
Although a non-zero value for the number of ticks spent doing IO
should imply a non-zero number of IOs in the interval test for
this explicitly to avoid a divide-by-zero in the event of bad
counter data.
libdm: test for zero interval_ns in _utilization() (Coverity)
It's possible for interval_ns to be zero if the interval is not
set or the clock is misconfigured. Test for this before using the
value as the divisor in the utilisation calculation.
Make it clear that the "aux data" presented in reports is the user
data stored in the field (and does not include any library-internal
state such as group descriptors) by renaming the field to user_data
and changing the heading to "UserData".
Make it clear in libdevmapper.h, and in function argument names, that
libdm-stats uses the aux_data field internally and that any values set
for user_data are appended to the library values before being stored
with a region, and similarly, that internal data fields will be stripped
prior to returning any previously stored user_data.
dmstats: replace --statstype with separate object switches
Replace --statstype=area,region,group with a separate switch for
each object type: --area, --region, --group. Omitting any object
type switch will use the defaults for the current command (regions
and groups for list, and regions, groups and areas for verbose list).
dmstats: use 'statsname' and 'groupid' in default fields
Replace the 'name' field with 'statsname' in order to report alias
names for groups, and include the 'group_id' field between statsname
and the 'region_id' field to make it clear to the user when groups
are in use.
Bryn M. Reeves [Mon, 13 Jun 2016 13:28:37 +0000 (14:28 +0100)]
dmstats: add stats_name field
To allow the names used to describe statistics report objects to
change (for e.g to support groups and region and group aliases)
introduce a new "stats_name" field that evaluates to the correct
name for the object being reported.
Bryn M. Reeves [Mon, 7 Mar 2016 18:07:57 +0000 (18:07 +0000)]
dmstats: add 'group' and 'ungroup' commands
Add a pair of commands to create and delete stats groups:
dmstats group --regions REGIONS
dmstats ungroup --groupid ID
REGIONS specifies a list of regions to be included in the group.
Regions are specified as a comma separated list in order of
increasing region ID. Ranges may be specified as a hypen separated
pair of values giving the first and last member of the range.
Bryn M. Reeves [Sun, 19 Jun 2016 12:30:46 +0000 (13:30 +0100)]
libdm: add stats group and region iterators and properties
Add support do dm_stats_walk*() to walk over the set of
available groups using the cursor embedded in the dm_stats
handle, and to obtain the type of the object at the current
stats cursor location. A set of flags is introduced to
control which objects are visited:
A final flag suppresses visits to regions that contain only a
single area - since the aggregate of such a region is idential
to the area it contains this allows these duplicates to be
filtered out:
DM_STATS_WALK_SKIP_SINGLE_AREA
If flags are not initialised before beginning a walk the default
set matches the behaviour of previous versions of the library.
Also accept group identifiers as immediate arguments to the
counter, metric, and property functions by adding control
flags to the region and area identifiers passed in.
Region and area properties are mapped to their equivalents for
the group (for example: group size is reported as the sum of
all regions contained in the group). Counter and metric values
are aggregated for the region or group.
Bryn M. Reeves [Thu, 16 Jun 2016 18:40:43 +0000 (19:40 +0100)]
libdm: use defined constants for buffer sizes
Introduce constants for the buffer sizes that libdm-stats uses:
one for messages sent to the kernel, one for rows of response data
returned, and a pair for the "start+len" range and histogram bounds
strings.
Bryn M. Reeves [Mon, 29 Feb 2016 17:52:29 +0000 (17:52 +0000)]
libdm: add statistics groups
Add a grouping facility to the libdm-stats library that allows the
user to bind several regions together as a group. Groups may be
used to aggregate data from several regions for reporting, or to
select and sort among large sets of regions.
A textual descriptor ("group tag") is associated with each group
and is stored in the first group member's aux_data field. The
tag contains the group member list and an optional alias for the
group, allowing the user to assign meaningful names to groups of
regions.
These descriptors are parsed in @stats_list message responses and
populate the resulting region and area tables with the group
structure.
Groups with overlapping regions are permitted but since this will
result in some events being counted more than once a warning is
printed in this case.
Nested and overlapping groups are not currently supported and
attempting to create these configurations results in error.
int dm_stats_get_metric(const struct dm_stats *dms, int metric,
uint64_t region_id, uint64_t area_id,
double *value);
This simplifies the implementation of value aggregation for
groups of regions. The named function interface now calls the
enum interface internally so that all new functionality is
available regardless of the method used to retrieve values.