Performance XK0-006 Practice Questions (Page 1)

Questions 1–5

1. 1expert · hard

   A server has 64 GB of RAM. The administrator runs `free -h` and sees: total=62G, used=58G, free=1.2G, buff/cache=2.8G, available=4.1G. A critical application is reporting OOM kills. The administrator checks `dmesg` and sees the OOM killer is targeting the application. The application's memory usage is stable at 50 GB. What is the MOST likely cause of the OOM kills?

   • AThe application has a memory leak and is slowly consuming more memory.
   • BAnother process is consuming memory, leaving insufficient memory for the application.
   • CThe system is using too much swap space.
   • DThe kernel's `vm.overcommit_memory` setting is set to 2, preventing overcommitment.
   Reveal Solution Discussion Select an answer first
2. 2expert · hard

   A storage administrator is troubleshooting a slow NFS server. The server exports a filesystem over a 10 GbE network. The administrator runs `iostat -x 1` and sees the local disk `sdb` has `%util`=90%, `await`=150ms, and `r_await`=180ms, `w_await`=20ms. The NFS clients report slow read performance. What is the MOST likely bottleneck?

   • AThe network is saturated.
   • BThe NFS server's CPU is overloaded.
   • CThe NFS clients are sending too many small requests.
   • DThe disk is the bottleneck for read operations.
   Reveal Solution Discussion Select an answer first
4. 3expert · hard

   A system administrator needs to generate a comprehensive performance report for a server that includes CPU, memory, and I/O statistics over the past week. The server has been running continuously. Which tool should the administrator use to generate this report?

   • A`iostat -x 5 10080`
   • B`top -b -n 1`
   • C`vmstat 5 10080`
   • D`sar -A -f /var/log/sa/sa$(date +%d) -o /tmp/report.txt`
   Reveal Solution Discussion Select an answer first
5. 4application · medium

   A database server is performing poorly. The administrator runs `iostat -x 1` and sees the following for the data disk: `%util`=85%, `await`=200ms, `svctm`=5ms. The disk is a single 10k RPM HDD. Which action would MOST improve performance?

   • AMove the database files to an SSD.
   • BReduce the database's memory allocation.
   • CUse `ionice -c 1 -n 0` on the database process.
   • DIncrease the disk's cache size.
   Reveal Solution Discussion Select an answer first
6. 5foundation · easy

   Which command displays a dynamic, real-time view of running processes and their CPU usage, updating every few seconds by default?

   • Atop
   • Biostat
   • Cps
   • Dfree
   Reveal Solution Discussion Select an answer first