4.9 KiB
job_object_helper requirements
job_object_helper is a module that wraps the Windows JobObject API, primarily for the purpose of limiting the amount of memory and CPU the current process can consume.
Exposed API
MOCKABLE_FUNCTION(, THANDLE(JOB_OBJECT_HELPER), job_object_helper_create);
MOCKABLE_FUNCTION(, int, job_object_helper_limit_memory, THANDLE(JOB_OBJECT_HELPER), job_object_helper, uint32_t, percent_physical_memory);
MOCKABLE_FUNCTION(, int, job_object_helper_limit_cpu, THANDLE(JOB_OBJECT_HELPER), job_object_helper, uint32_t, percent_cpu);
job_object_helper_create
MOCKABLE_FUNCTION(, THANDLE(JOB_OBJECT_HELPER), job_object_helper_create);
job_object_helper_create is used to create a JOB_OBJECT_HELPER object.
SRS_JOB_OBJECT_HELPER_18_016: [ job_object_helper_create shall allocate a JOB_OBJECT_HELPER object. ]
SRS_JOB_OBJECT_HELPER_18_023: [ job_object_helper_create shall call GlobalMemoryStatusEx to get the total amount of physical memory in kb. ]
SRS_JOB_OBJECT_HELPER_18_024: [ job_object_helper_create shall call CreateJobObject to create a new job object passing NULL for both lpJobAttributes and lpName. ]
SRS_JOB_OBJECT_HELPER_18_025: [ job_object_helper_create shall call GetCurrentProcess to get the current process handle. ]
SRS_JOB_OBJECT_HELPER_18_026: [ job_object_helper_create shall call AssignProcessToJobObject to assign the current process to the new job object. ]
SRS_JOB_OBJECT_HELPER_18_027: [ job_object_helper_create shall call CloseHandle to close the handle of the current process. ]
SRS_JOB_OBJECT_HELPER_18_018: [ If there are any failures, job_object_helper_create shall fail and return NULL. ]
SRS_JOB_OBJECT_HELPER_18_019: [ job_object_helper_create shall succeed and return the JOB_OBJECT_HELPER object. ]
job_object_helper_dispose
static void job_object_helper_dispose(JOB_OBJECT_HELPER* job_object_helper);
job_object_helper_dispose frees all of the resources used by the JOB_OBJECT_HELPER object.
SRS_JOB_OBJECT_HELPER_18_033: [ job_object_helper_dispose shall call CloseHandle to close the handle to the job object. ]
job_object_helper_limit_memory
MOCKABLE_FUNCTION(, int, job_object_helper_limit_memory, THANDLE(JOB_OBJECT_HELPER), job_object_helper, uint32_t, percent_physical_memory);
job_object_helper_limit_memory limits the amount of physical memory available to the current progess.
SRS_JOB_OBJECT_HELPER_18_035: [ If job_object_helper is NULL, job_object_helper_limit_memory shall fail and return a non-zero value. ]
SRS_JOB_OBJECT_HELPER_18_036: [ If percent_physical_memory is 0, job_object_helper_limit_memory shall fail and return a non-zero value. ]
SRS_JOB_OBJECT_HELPER_18_037: [ If percent_physical_memory is greater than 100, job_object_helper_limit_memory shall fail and return a non-zero value. ]
SRS_JOB_OBJECT_HELPER_18_039: [* job_object_helper_limit_memory shall call SetInformationJobObject, passing JobObjectExtendedLimitInformation and a JOBOBJECT_EXTENDED_LIMIT_INFORMATION object with JOB_OBJECT_LIMIT_JOB_MEMORY set and JobMemoryLimit set to the percent_physical_memory percent of the physical memory in bytes. ]
SRS_JOB_OBJECT_HELPER_18_041: [ If there are any failures, job_object_helper_limit_memory shall fail and return a non-zero value. ]
SRS_JOB_OBJECT_HELPER_18_042: [ job_object_helper_limit_memory shall succeed and return 0. ]
job_object_helper_limit_cpu
MOCKABLE_FUNCTION(, int, job_object_helper_limit_cpu, THANDLE(JOB_OBJECT_HELPER), job_object_helper, uint32_t, percent_cpu);
job_object_helper_limit_cpu limits the amount of CPU available to the current process.
SRS_JOB_OBJECT_HELPER_18_043: [ If job_object_helper is NULL, job_object_helper_limit_cpu shall fail and return a non-zero value. ]
SRS_JOB_OBJECT_HELPER_18_044: [ If percent_cpu is 0, job_object_helper_limit_cpu shall fail and return a non-zero value. ]
SRS_JOB_OBJECT_HELPER_18_045: [ If percent_cpu is greater than 100, job_object_helper_limit_cpu shall fail and return a non-zero value. ]
SRS_JOB_OBJECT_HELPER_18_047: [ job_object_helper_limit_cpu shall call SetInformationJobObject passing JobObjectCpuRateControlInformation and a JOBOBJECT_CPU_RATE_CONTROL_INFORMATION object with JOB_OBJECT_CPU_RATE_CONTROL_ENABLE and JOB_OBJECT_CPU_RATE_CONTROL_HARD_CAP set, and CpuRate set to percent_cpu times 100. ]
SRS_JOB_OBJECT_HELPER_18_049: [ If there are any failures, job_object_helper_limit_cpu shall fail and return a non-zero value. ]
SRS_JOB_OBJECT_HELPER_18_050: [ job_object_helper_limit_cpu shall succeed and return 0. ]