Windows® Internals, Sixth Edition, Part 1

In the following sample output from Kernrate, Windows Media Player was running, playing a recorded movie from disk:C:\WinDDK\7600.16385.1\tools\Other\i386>kernrate.exe /==============================\ < KERNRATE LOG > \==============================/ Date: 2011/03/09 Time: 16:44:24 Machine Name: TEST-LAPTOP Number of Processors: 2 PROCESSOR_ARCHITECTURE: x86 PROCESSOR_LEVEL: 6 PROCESSOR_REVISION: 0f06 Physical Memory: 3310 MB Pagefile Total: 7285 MB Virtual Total: 2047 MB PageFile1: \??\C:\pagefile.sys, 4100MB OS Version: 6.1 Build 7601 Service-Pack: 1.0 WinDir: C:\Windows Kernrate Executable Location: C:\WINDDK\7600.16385.1\TOOLS\OTHER\I386 Kernrate User-Specified Command Line: kernrate.exe Kernel Profile (PID = 0): Source= Time, Using Kernrate Default Rate of 25000 events/hit Starting to collect profile data ***> Press ctrl-c to finish collecting profile data ===> Finished Collecting Data, Starting to Process Results ------------Overall Summary:-------------- P0 K 0:00:00.000 ( 0.0%) U 0:00:00.234 ( 4.7%) I 0:00:04.789 (95.3%) DPC 0:00:00.000 ( 0.0%) Interrupt 0:00:00.000 ( 0.0%) Interrupts= 9254, Interrupt Rate= 1842/sec. P1 K 0:00:00.031 ( 0.6%) U 0:00:00.140 ( 2.8%) I 0:00:04.851 (96.6%) DPC 0:00:00.000 ( 0.0%) Interrupt 0:00:00.000 ( 0.0%) Interrupts= 7051, Interrupt Rate= 1404/sec. TOTAL K 0:00:00.031 ( 0.3%) U 0:00:00.374 ( 3.7%) I 0:00:09.640 (96.0%) DPC 0:00:00.000 ( 0.0%) Interrupt 0:00:00.000 ( 0.0%) Total Interrupts= 16305, Total Interrupt Rate= 3246/sec. Total Profile Time = 5023 msec BytesStart BytesStop BytesDiff. Available Physical Memory , 1716359168, 1716195328, -163840 Available Pagefile(s) , 5973733376, 5972783104, -950272 Available Virtual , 2122145792, 2122145792, 0 Available Extended Virtual , 0, 0, 0 Committed Memory Bytes , 1665404928, 1666355200, 950272 Non Paged Pool Usage Bytes , 66211840, 66211840, 0 Paged Pool Usage Bytes , 189083648, 189087744, 4096 Paged Pool Available Bytes , 150593536, 150593536, 0 Free System PTEs , 37322, 37322, 0 Total Avg. Rate Context Switches , 30152, 6003/sec. System Calls , 110807, 22059/sec. Page Faults , 226, 45/sec. I/O Read Operations , 730, 145/sec. I/O Write Operations , 1038, 207/sec. I/O Other Operations , 858, 171/sec. I/O Read Bytes , 2013850, 2759/ I/O I/O Write Bytes , 28212, 27/ I/O I/O Other Bytes , 19902, 23/ I/O ----------------------------- Results for Kernel Mode: ----------------------------- OutputResults: KernelModuleCount = 167 Percentage in the following table is based on the Total Hits for the Kernel Time 3814 hits, 25000 events per hit -------- Module Hits msec %Total Events/Sec NTKRNLPA 3768 5036 98 % 18705321 NVLDDMKM 12 5036 0 % 59571 HAL 12 5036 0 % 59571 WIN32K 10 5037 0 % 49632 DXGKRNL 9 5036 0 % 44678 NETW4V32 2 5036 0 % 9928 FLTMGR 1 5036 0 % 4964 ================================= END OF RUN ================================== ============================== NORMAL END OF RUN ==============================

The overall summary shows that the system spent 0.3 percent of the time in kernel mode, 3.7 percent in user mode, 96.0 percent idle, 0.0 percent at DPC level, and 0.0 percent at interrupt level. The module with the highest hit rate was Ntkrnlpa.exe, the kernel for machines with Physical Address Extension (PAE) or NX support. The module with the second highest hit rate was nvlddmkm.sys, the driver for the video card on the machine used for the test. This makes sense because the major activity going on in the system was Windows Media Player sending video I/O to the video driver.