mirror of https://github.com/citusdata/citus.git
Fix typos
parent
c3d1ad3f9d
commit
fa56e38033
|
@ -2390,7 +2390,7 @@ Cost and capacity are vague on purpose, this way users can choose their own
|
|||
way to determine cost of a shard group, but **in practice "cost" is usually
|
||||
disk size** (because `by_disk_size` is the default rebalance strategy).
|
||||
Capacity is almost always set to 1, because almost all Citus clusters are
|
||||
homogenous (they contain the same nodes, except for maybe the coordinator). The
|
||||
homogeneous (they contain the same nodes, except for maybe the coordinator). The
|
||||
main usage for "Is a shard group allowed on a certain node?" is to be able to pin a
|
||||
specific shard group to a specific node.
|
||||
|
||||
|
@ -2432,7 +2432,7 @@ Of course, the devil is in the details though.
|
|||
### When is the balance better?
|
||||
|
||||
The main way to determine if the balance is better is by comparing the
|
||||
utilization of node A and B, before and ofter the move and seeing if they are
|
||||
utilization of node A and B, before and after the move and seeing if they are
|
||||
net closer to the average utilization of the nodes in the cluster. The easiest
|
||||
way to explain this is with a simple example:
|
||||
|
||||
|
@ -2459,8 +2459,8 @@ moving shards around isn't free.
|
|||
this threshold is that these small differences in utilization are not
|
||||
necessarily problematic and might very well resolve automatically over time. For example, consider a scenario in which
|
||||
one shard gets mostly written in during the weekend, while another one during
|
||||
the week. Moving shards on monday and that you then have to move back on
|
||||
friday is not very helpful given the overhead of moving data around.
|
||||
the week. Moving shards on Monday and that you then have to move back on
|
||||
Friday is not very helpful given the overhead of moving data around.
|
||||
- `improvement_threshold`: This is used in cases where a shard group move from
|
||||
node A to B swaps which node now has the highest utilization (so afterwards B
|
||||
will have higher utilization than A). As described above this can still
|
||||
|
@ -2572,7 +2572,7 @@ the full rebalance, and each of its tasks are separate shard group moves.
|
|||
|
||||
### Parallel background task execution
|
||||
|
||||
A big benefit of the bacground task infrastructure is that it can execute tasks
|
||||
A big benefit of the background task infrastructure is that it can execute tasks
|
||||
and jobs in parallel. This can make rebalancing go much faster especially in
|
||||
clusters with many nodes. To ensure that we're not doing too many tasks in
|
||||
parallel though we have a few ways to limit concurrency:
|
||||
|
|
Loading…
Reference in New Issue