Synnefo » snf-ganeti

tryAlloc: restrict valid node pairs to same-group

This is a cheap way to make capacity calculation work well with
multi-group clusters.

There are two alternatives in implementing this:

- we can split the cluster into groups, run individual group
allocation, and then try to recombine the groups; but this doesn't...

Convert node evacuation to multi-group

This patch does the necessary changes to make the new tryMGEvac work
correctly: each instance remains inside its primary node's group when
it is evacuated.

This is done by splitting up the to-be-evacuated instance list per...

Instance relocation: stay within the current group

This patch adds a new top-level relocation function that restricts the
relocation to the instance's group, and switches hail to it.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Balazs Lecz <leczb@google.com>

Parallelize the balancing computations

This small patch changes the balancing computation to work in
parallel, if possible.

While the normal linking is against the single-threaded runtime, if
the code is linked against the multi-threaded one, the balancing will...

Fix updating of available (V)CPUs in CStats

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Balazs Lecz <leczb@google.com>

Merge branch 'stable-0.2'

• devel-0.2:
  Update NEWS file for 0.2.8 release
  hbal: return meaningful exit code for job failures
  Change the balancing function

Move some tiered spec functionality to Cluster.hs

This splits out a bit of code from hspace.hs and moves it into its own
function in Cluster.hs.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Balazs Lecz <leczb@google.com>

hail: display group names in info messages

This patch switches from the group index to the group name for the
informational messages in the hail results.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Balazs Lecz <leczb@google.com>

Improve error reporting for small clusters

When doing a two-node allocation on a cluster/group in which only one
node is online, or a one-node allocation without any online nodes, we
didn't show a valid error mesage. The patch changes tryAlloc to "fail
hard" in this case, to make the failure explicit....

Add a 'log' attribute to allocation solutions

And also a couple of functions for describing a given solution; these
will be used in the future instead of the ones currently in hail.

The patch also enhances the description of failure messages.

Signed-off-by: Iustin Pop <iustin@google.com>...

Cleanup AllocSolution after AllocElement changes

Since we added the score to AllocElement, we don't need to wrap
AllocElement in yet another tuple, just to attach the cluster score. So
we simplify the AllocSolution type.

Signed-off-by: Iustin Pop <iustin@google.com>...

Add two utility functions for the Result type

Actually, this just moves the functions from the QC module to Types, and
removes a duplicate entry from Cluster.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Balazs Lecz <leczb@google.com>

Add two functions for checking cluster consistency

For now, we don't support instances allocated across two groups, and we
will reject such clusters. The isClusterConsistent function will return
a list of inconsistent instances, potentially allowing operation without...

Use the mingain options in the balancing algorithm

Also adds them in hbal.

hail: fix error message for failed multi-evac

Currently we show the instance index, but this makes no sense outside
the current running program. Instead, we show the instance name.

Introduce per-metric weights

Currently all metrics have the same weight (we just sum them together).
However, for the hard constraints (N+1 failures, offline nodes, etc.)
we should handle the metrics differently based on their meaning. For
example, an instance living on a primary offline node is worse than an...

hbal: print short names in steps list

This was a regression from the name handling changes, as we started
using the original names for the solution list (which is not designed
for parsing/feeding back into ganeti).

Allow '+' in node list fields

When the field list is prefixed with a plus sign, this will extend the
default field list, instead of replacing it entirely.

Move two functions from hspace to Cluster.hs

This is done so we can test a longer pipeline.

Stop modifying names for internal computations

Currently the name used internally is modified and holds the shortened
name of the nodes/instances. This has caused issues before, since we
always have to strip the suffix from input data and reapply it if we...

Fix hspace's KM metrics

We returned the KM_POOL_* metrics as the final state, not as the delta
between the final and the initial state.

Introduce total vcpu tracking in CStats

We add a new field that tracks the available virtual cpus (expressed as
node cpus times the vcpu ratio).

balance function: use the movable flag directly

Instead of deciding based on secondary node, use the new flag.

Move a type declaration to Node.hs

We'll need AllocElement in both Cluster and IAlloc in the future, so we
move it to Node.hs which is imported by both.

Signed-off-by: Iustin Pop <iustin@google.com>

Implement evacuation mode in hbal

This mode restricts the list of instances to be moved to the instances
living on the offline (and drained) nodes.

Signed-off-by: Iustin Pop <iustin@google.com>

Split the balancing function in two parts

Currently in the balancing function we do two thing:

- take the decision where to do a new balancing round or not
- and actually computing the balancing round

This is not nice, as the two parts are conceptually separate, so this...

Metric: count of primary instances/offline nodes

This helps with evacuation/failover of instances on 2-node clusters with
one one offline.

Use conflicting primaries count in cluster score

This small patch adds the number of conflicting primaries in the cluster
score. This is different from the other non-CV metrics where we usually
compute the percentage of failing instances (for that metric); but for a...

Move more node-listing functionality in Node.hs

This will prepare for the runtime-selectable field list.

Expand the --print-instances output

This adds run status, resource parameters and load parameters for
instances.

Simplify Cluster.computeMoves

Since we now have an actual type for describing the instance moves
(IMove), it's simpler to convert this into the move description/move
commands, rather than re-computing the move based on initial and final
nodes. This makes the shell commands computation and over-Luxi command...

Generalise the node/instance listing

This patch introduces a generic formatTable function (based on, and
similar to the Ganeti one, but different and more FP in style) and
changes the node and instance listing to it.

The node list (due to the many variables) is still a little bit hackish...

Start using the utilisation scores in balancing

This enables the per-node load/total available capacity scores to be
used in balancing. Note that the total available capacity is currently
fixed at zero and cannot be changed by the user.

Allow displaying the instance map in hbal

This is similar to --print-nodes, but with much fewer fields.

Style change: node and instance attributes

This changes from a_b to aB in all node and instance attributes, to
match the standard Haskell style. Also attributes that should have been
camel-cased but weren't were changed (e.g. plist → pList, pnode →
pNode).

Change iMoveToJob to properly create migrates

The current Cluster.iMoveToJob always creates failovers, which is not
what we want. This simply used the original instances status to select
between these two (this is not optimal by the way, since the status...

Store the instance move in the MoveJobs

This will automatically sort our Ganeti jobs into the independent job
sets, and then we can submit them separately.

Add a function converting Placements into Jobs

This converts from htools-specific Placements into Ganeti standard
OpCodes, which will later allow execution via Luxi.

hbal: Implement grouping of moves into jobsets

Since moving two instances between different node-quadruples (inst X: A,
B → C, D and inst Y: E, F → G, H) can be parallelised by Ganeti, it
makes sense to split the operation list into jobsets whose execution...

Split the balancing algorithm in two parts

Currently the computation, recursing part and the IO part (progress
updates) of the balancing main function (iterateDepth) are all in the
same function, which makes it hard to test. This patch moves the
decision/computation part (whether to proceed one more round, whether we...

Use migrate or failover based on instance state

While we can't guarantee that the instance will be in the same state by
the time the migrate/failover command will be run, we can at least try
to do the right thing assuming no other changes to the cluster state....

Fix a haddoc issue

Change the tryAlloc/tryReloc workflow

Currently, the tryAlloc and tryReloc function return a list with all the
results, both failures and successes. This is fine for hail, which does
one round of allocations, but is not so good for hspace, which does
iterative rounds; since at each (successful) step we only take the best...

Slight change to the internal allocation results

Currently the Cluster.AllocSolution type is defined as a list of
‘(OpResult Node.list, …)’ and the results for applyMove are defined as
‘(OpResult Node.List, …)’. Both these means that the failure/success
indication is hidden in the first elements of this tuple, which makes is...

Export more stats in hspace

This patch changes Cluster.totalResources to compute more resources and
prints them in hspace.

Simplify Cluster.computeMoves

This patch changes the function Cluster.computeMoves to use guards and a
couple of subexpressions in order to greatly simplify it.

Introduce a new type for allocation results

Currently the allocation/move operations workflow return ‘Maybe a’,
which is very convenient but loses all details about the failure mode.

This patch introduces a new data type which encodes the specific failure...

Fix totalResources avail disk computation

This uses the newly-added Node.availDisk to compute the actual available
disk correctl, and display the total allocatable disk in hspace.

Add display of more stats in hspace

This patch changes Cluster.totalResources to compute more details about
the cluster status, and enhances hspace to display more of these.

Fix the various monomorphism warning

In a few places (e.g. tryRead or any printf call) it's a little bit hard
to add the correct type signatures, but in the it is possible to fix
these warnings (which can bite one in subtle cases).