Package org.apache.solr.search

Class MemAllowedLimit

java.lang.Object
org.apache.solr.search.MemAllowedLimit
All Implemented Interfaces:
org.apache.lucene.index.QueryTimeout, QueryLimit
public class MemAllowedLimit extends Object implements QueryLimit
Enforces a memory-based limit on a given SolrQueryRequest, as specified by the memAllowed query parameter.

This class tracks per-thread memory allocations during a request using its own ThreadLocal. It records the current thread allocation when the instance was created (typically at the start of SolrQueryRequest processing) as a starting point, and then on every call to shouldExit() it accumulates the amount of reported allocated memory since the previous call, and compares the accumulated amount to the configured threshold, expressed in mebi-bytes.

NOTE: this class accesses com.sun.management.ThreadMXBean#getCurrentThreadAllocatedBytes using reflection. On JVM-s where this implementation is not available an exception will be thrown when attempting to use the memAllowed parameter.

  • Constructor Details

  • Method Details

    • shouldExit

      public boolean shouldExit()
      Specified by:
      shouldExit in interface org.apache.lucene.index.QueryTimeout

    • currentValue

      public Object currentValue()
      Description copied from interface: QueryLimit
      A value representing the portion of the specified limit that has been consumed. Reading this value should never affect the outcome (other than the time it takes to do it).
      Specified by:
      currentValue in interface QueryLimit
      Returns:
      an expression of the amount of the limit used so far, numeric if possible, if non-numeric it should have toString() suitable for logging or similar expression to the user.