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+# taskset(1)
+
+Set cpu affinity for new processes or already running ones.
+
+```sh
+# Pin all (-a) tasks of new command on cores 0,1,2,4.
+taskset -ac 0-2,4 CMD [ARGS]
+
+# Pin all tasks of running PID onto cores 0,2,4.
+taskset -ac 0-5:2 -p PID
+```
+
+### Example
+Utility script to extract cpu lists grouped by the last-level-cache.
+```python
+import subprocess
+
+res = subprocess.run(["lscpu", "-p=cpu,cache"], capture_output=True, check=True)
+
+LLC2CPU = dict()
+
+for line in res.stdout.decode().splitlines():
+    if line.startswith("#"):
+        continue
+
+    cpu, cache = line.split(",")
+    llc        = cache.split(":")[-1]
+
+    LLC2CPU.setdefault(llc, list()).append(int(cpu))
+
+LLC2RANGE = dict()
+
+for llc, cpus in LLC2CPU.items():
+    first_cpu = cpus[0]
+    prev_cpu  = cpus[0]
+    for cpu in cpus[1:]:
+        if cpu != prev_cpu + 1:
+            LLC2RANGE.setdefault(llc, list()).append(f"{first_cpu}-{prev_cpu}")
+            # New range begins.
+            first_cpu = cpu
+        prev_cpu = cpu
+    # Trailing range.
+    LLC2RANGE.setdefault(llc, list()).append(f"{first_cpu}-{prev_cpu}")
+
+print(LLC2RANGE)
+```