A process or thread is implemented to issue a command which executes without use of a processor that issues the command, retain control of the processor to check whether the issued command has completed, and when the issued command has not completed repeat the checking without relinquishing the processor, until a limiting condition is satisfied. The limiting condition may be determined specifically for a current execution of the command, based on one or more factors, such as durations of executions of the command after start of the process or thread and/or an indicator of delay in a current execution of the command. When the limiting condition is satisfied, the processor is relinquished by the process or thread issuing a sleep command, after setting an interrupt. After the command completes, the limiting condition is determined anew based on the duration of the current execution, for use in a next execution.