Major Description
We have seen a repeat of long running rgc remove operations - similarly to what was described in OAK-8351.
This time happening with the query generated by queryForDefaultNoBranch with the query shape for example similar to:
{
"_sdType" : 70,
"_sdMaxRevTime" : {
"$lt" : NumberLong(1603030303)
},
"$or" : [
{
"$or" : [
{
"_id" : /.*-1\/0/
},
{
"_id" : /[^-]*/,
"_path" : /.*-1\/0/
}
],
"_sdMaxRevTime" : {
"$lt" : NumberLong(1602020202)
}
},
{
"$or" : [
{
"_id" : /.*-2\/0/
},
{
"_id" : /[^-]*/,
"_path" : /.*-2/0/
}
],
"_sdMaxRevTime" : {
"$lt" : NumberLong(1601010101)
}
}
}
While setting an index filter with the query plan in mongodb is one option, we could additionally also look into simplifying the above query further into multiple queries : eg. by having 1 query per clusterNodeId, and then simplifying the _sdMaxRevTime accordingly, so that the above would translate into the following 2 queries (with the hope that mongodb finds the optimal query plan) :
{
"_sdType" : 70,
"_sdMaxRevTime" : {
"$lt" : NumberLong(1602020202)
},
"$or" : [
{
"_id" : /.*-1\/0/
},
{
"_id" : /[^-]*/,
"_path" : /.*-1\/0/
}
}
}
and
{
"_sdType" : 70,
"_sdMaxRevTime" : {
"$lt" : NumberLong(1601010101)
},
"$or" : [
{
"_id" : /.*-2\/0/
},
{
"_id" : /[^-]*/,
"_path" : /.*-2\/0/
}
}
}