Ticket #3421: mythtv_jobqueue_ionice.diff

File mythtv_jobqueue_ionice.diff, 6.5 KB (added by rd.mora@…, 17 years ago)

Patch to set I/O nice level to idle on jobqueue processes (not production ready)

  • libs/libmythtv/jobqueue.cpp

     
    488488            }
    489489        }

  • libs/libmyth/util.cpp 

    -        if (startedJobAlready)
-            sleep(5);
-        else
-            sleep(sleepTime);
+        sleep(sleepTime);
     }
 }

@@ -1775,2 +1772,2 @@
         path = tokens[0];
     }

+    int flags = 0;
     if (jobQueueCPU < 2)
-        nice(17);
+    {
+        flags = MYTH_SYSTEM_IOPRIO_IDLE;
+        flags |= MYTH_SYSTEM_NICE_LOW_PRIO;
+    }

     QString transcoderName;
     if (transcoder == RecordingProfile::TranscoderAutodetect)
@@ -1836,2 +1837,2 @@
         VERBOSE(VB_JOBQUEUE, LOC + QString("Running command: '%1'")
                                            .arg(command));

-        int result = myth_system(command);
+        int result = myth_system(command, flags);
         int status = GetJobStatus(jobID);

         if ((result == MYTHSYSTEM__EXIT__EXECL_ERROR) ||
@@ -2023,2 +2024,2 @@
         path = tokens[0];
     }

+    int flags = 0;
+    switch (jobQueueCPU)
+    {
+        case  0: flags = MYTH_SYSTEM_IOPRIO_IDLE;
+                 flags |= MYTH_SYSTEM_NICE_LOW_PRIO;
+                 break;
+        case  1: flags = MYTH_SYSTEM_IOPRIO_IDLE;
+                 flags |= MYTH_SYSTEM_NICE_MEDIUM_PRIO;
+                 break;
+        case  2:
+        default: break;
+    }
+
     VERBOSE(VB_JOBQUEUE, LOC + QString("Running command: '%1'").arg(command));

-    breaksFound = myth_system(command);
+    breaksFound = myth_system(command, flags);
     int priority = LP_NOTICE;
     QString comment = "";

@@ -2121,2 +2135,2 @@
     gContext->LogEntry("jobqueue", LP_NOTICE,
                        QString("Job \"%1\" Started").arg(jobDesc), msg);

+    int flags = 0;
     switch (jobQueueCPU)
     {
-        case  0: nice(17);
+        case  0: flags = MYTH_SYSTEM_IOPRIO_IDLE;
+                 flags |= MYTH_SYSTEM_NICE_LOW_PRIO;
                  break;
-        case  1: nice(10);
+        case  1: flags = MYTH_SYSTEM_IOPRIO_IDLE;
+                 flags |= MYTH_SYSTEM_NICE_MEDIUM_PRIO;
                  break;
         case  2:
         default: break;
@@ -2134,2 +2151,2 @@
     VERBOSE(VB_JOBQUEUE, LOC + QString("Running command: '%1'")
                                        .arg(runningJobCommands[key]));

-    int result = myth_system(runningJobCommands[key]);
+    int result = myth_system(runningJobCommands[key], flags);

     if ((result == MYTHSYSTEM__EXIT__EXECL_ERROR) ||
         (result == MYTHSYSTEM__EXIT__CMD_NOT_FOUND))
     
    5252#include "jsmenuevent.h"
    5353#endif

  • libs/libmyth/util.h 

    +// @TODO: make this a configure option
+#define USE_IOPRIO_IDLE
+#ifdef USE_IOPRIO_IDLE
+// From /usr/src/linux/Documentation/block/ioprio.txt
+#include <asm/unistd.h>
+extern int sys_ioprio_set(int, int, int);
+extern int sys_ioprio_get(int, int);
+
+#if defined(__i386__)
+#define __NR_ioprio_set         289
+#define __NR_ioprio_get         290
+#elif defined(__ppc__)
+#define __NR_ioprio_set         273
+#define __NR_ioprio_get         274
+#elif defined(__x86_64__)
+#define __NR_ioprio_set         251
+#define __NR_ioprio_get         252
+#elif defined(__ia64__)
+#define __NR_ioprio_set         1274
+#define __NR_ioprio_get         1275
+#else
+#error "Unsupported arch"
+#endif
+
+_syscall3(int, ioprio_set, int, which, int, who, int, ioprio);
+_syscall2(int, ioprio_get, int, which, int, who);
+
+enum {
+        IOPRIO_CLASS_NONE,
+        IOPRIO_CLASS_RT,
+        IOPRIO_CLASS_BE,
+        IOPRIO_CLASS_IDLE,
+};
+
+enum {
+        IOPRIO_WHO_PROCESS = 1,
+        IOPRIO_WHO_PGRP,
+        IOPRIO_WHO_USER,
+};
+
+#define IOPRIO_CLASS_SHIFT      13
+#endif /* USE_IOPRIO_IDLE */
+
 /** \fn mythCurrentDateTime()
  *  \brief Returns the current QDateTime object, stripped of its msec component
  */
@@ -250,2 +293,2 @@
         if (fd != 0)
             close(fd);

+#ifdef USE_IOPRIO_IDLE
+        /* Set io priority if required */
+        if(flags & MYTH_SYSTEM_IOPRIO_IDLE)
+            if(ioprio_set(IOPRIO_WHO_PROCESS, 0, 7 | IOPRIO_CLASS_IDLE << IOPRIO_CLASS_SHIFT) == -1)
+                VERBOSE(VB_IMPORTANT, "Error setting IO Priority!");
+#endif
+
+        if (((flags & MYTH_SYSTEM_NICE_MEDIUM_PRIO) && setpriority(PRIO_PROCESS, 0, 10)) ||
+            ((flags & MYTH_SYSTEM_NICE_LOW_PRIO) && setpriority(PRIO_PROCESS, 0, 19)))
+            VERBOSE(VB_IMPORTANT, "Setting priority of child process failed.");
+
         /* Run command */
         execl("/bin/sh", "sh", "-c", QString(command.utf8()).ascii(), NULL);
         if (errno)

  • programs/mythbackend/housekeeper.cpp 

     #include "mythexp.h"

-#define MYTH_SYSTEM_DONT_BLOCK_LIRC          0x1 //< myth_system() flag to avoid blocking
-#define MYTH_SYSTEM_DONT_BLOCK_JOYSTICK_MENU 0x2 //< myth_system() flag to avoid blocking
+#define MYTH_SYSTEM_DONT_BLOCK_LIRC          0x01 //< myth_system() flag to avoid blocking
+#define MYTH_SYSTEM_DONT_BLOCK_JOYSTICK_MENU 0x02 //< myth_system() flag to avoid blocking
+#define MYTH_SYSTEM_IOPRIO_IDLE              0x04 //< myth_system() flag to use idle io priority
+#define MYTH_SYSTEM_NICE_LOW_PRIO            0x08 //< myth_system() nice child to low priority (19)
+#define MYTH_SYSTEM_NICE_MEDIUM_PRIO         0x10 //< myth_system() nice child to medium priority (10)

 class QPixmap;
 class QImage;
     
    312312        command = QString("%1 %2 >>%3 2>&1").arg(mfpath).arg(mfarg).arg(mflog);