1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
|
/**
* Test the balancerCollectionStatus command and its possible outputs
*/
(function() {
'use strict';
const chunkSizeMB = 1;
let st = new ShardingTest({
shards: 3,
other: {
// Set global max chunk size to 1MB
chunkSize: chunkSizeMB
}
});
function runBalancer() {
st.startBalancer();
// Let the balancer run until balanced.
st.printShardingStatus(true);
st.awaitBalance('col', 'db');
st.printShardingStatus(true);
st.stopBalancer();
}
// only fully quilified namespaces are allowed on the command
assert.commandFailedWithCode(st.s0.adminCommand({balancerCollectionStatus: 'db'}),
ErrorCodes.InvalidNamespace);
// only sharded databases are allowed
assert.commandFailedWithCode(st.s0.adminCommand({balancerCollectionStatus: 'db.col'}),
ErrorCodes.NamespaceNotSharded);
// setup the collection for the test
assert.commandWorked(st.s0.adminCommand({enableSharding: 'db'}));
assert.commandWorked(st.s0.adminCommand({shardCollection: 'db.col', key: {key: 1}}));
// only sharded collections are allowed
assert.commandWorked(st.s0.getDB('db').runCommand({create: "col2"}));
assert.commandFailedWithCode(st.s0.adminCommand({balancerCollectionStatus: 'db.col2'}),
ErrorCodes.NamespaceNotSharded);
let result = assert.commandWorked(st.s0.adminCommand({balancerCollectionStatus: 'db.col'}));
// new collections must be balanced
assert.eq(result.balancerCompliant, true);
// get shardIds
const shards = st.s0.getDB('config').shards.find().toArray();
const bigString = 'X'.repeat(1024 * 1024); // 1MB
for (var i = 0; i < 30; i += 10) {
assert.commandWorked(st.s0.getDB('db').getCollection('col').insert({key: i, s: bigString}));
}
// manually split and place the 3 chunks on the same shard
assert.commandWorked(st.s0.adminCommand({split: 'db.col', middle: {key: 10}}));
assert.commandWorked(st.s0.adminCommand({split: 'db.col', middle: {key: 20}}));
assert.commandWorked(st.s0.adminCommand({moveChunk: 'db.col', find: {key: 0}, to: shards[0]._id}));
assert.commandWorked(st.s0.adminCommand({moveChunk: 'db.col', find: {key: 10}, to: shards[0]._id}));
assert.commandWorked(st.s0.adminCommand({moveChunk: 'db.col', find: {key: 20}, to: shards[0]._id}));
// check the current status
result = assert.commandWorked(st.s0.adminCommand({balancerCollectionStatus: 'db.col'}));
// chunksImbalanced expected
assert.eq(result.balancerCompliant, false);
assert.eq(result.firstComplianceViolation, 'chunksImbalance');
// run balancer until balanced
runBalancer();
// manually move a chunk to a shard before creating zones (this will help
// testing the zone violation)
assert.commandWorked(st.s0.adminCommand({moveChunk: 'db.col', find: {key: 10}, to: shards[2]._id}));
// create zones on first two shards only
assert.commandWorked(st.s0.adminCommand({addShardToZone: shards[0]._id, zone: 'zone0'}));
assert.commandWorked(st.s0.adminCommand(
{updateZoneKeyRange: 'db.col', min: {key: MinKey}, max: {key: 10}, zone: 'zone0'}));
assert.commandWorked(st.s0.adminCommand({addShardToZone: shards[1]._id, zone: 'zone1'}));
assert.commandWorked(st.s0.adminCommand(
{updateZoneKeyRange: 'db.col', min: {key: 10}, max: {key: 20}, zone: 'zone1'}));
result = assert.commandWorked(st.s0.adminCommand({balancerCollectionStatus: 'db.col'}));
// having a chunk on a different zone will cause a zone violation
assert.eq(result.balancerCompliant, false);
assert.eq(result.firstComplianceViolation, 'zoneViolation');
// run balancer until balanced
runBalancer();
assert.eq(result.chunkSize, chunkSizeMB);
st.stop();
})();
|
