Performance issue querying process instances by variable name and value

Issue

We are seeing slow response times when fetching process instances by variable name and value. The DBA noticed the following slow sql, taking several seconds during a load test:

select processins0_.processInstanceId as col_0_0_, processins0_.processId as col_1_0_, processins0_.processName as col_2_0_, processins0_.processVersion as col_3_0_, processins0_.status ascol_4_0_, processins0_.externalId as col_5_0_, processins0_.start_date as col_6_0_, processins0_.user_identity as col_7_0_, processins0_.processInstanceDescription as col_8_0_, processins0_.correlationKey as col_9_0_, processins0_.parentProcessInstanceId as col_10_0_ from ProcessInstanceLog processins0_ where (processins0_.status in (? , ?)) and(processins0_.processInstanceId in (select variablein1_.processInstanceId from VariableInstanceLog variablein1_ where variablein1_.variableId=? and (variablein1_.value like ?) and(variablein1_.id in (select max(variablein2_.id) from VariableInstanceLog variablein2_ where variablein2_.variableId=variablein1_.variableId group by variablein2_.processInstanceId)))) and(processins0_.externalId in (? , ? , ..., ?)) order by processins0_.processInstanceId ASC limit ?
0.27 / min4.16 s