<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta content="text/html;charset=ISO-8859-1" http-equiv="Content-Type"> </head> <body bgcolor="#ffffff" text="#000000"> Hi Dan, Thanks for the prompt response. But why the arc misses if I repeat the du and why is the L2arc size from arcstat much bigger than from zpool iostat? Dan McDonald wrote: <blockquote cite="mid:2564F2CB-C602-42EA-8A16-CA54A45088C6@omniti.com" type="cite"> <blockquote type="cite"> <pre wrap="">On Mar 17, 2017, at 4:12 AM, Richard Skelton <a class="moz-txt-link-rfc2396E" href="mailto:skeltonr@btconnect.com"><skeltonr@btconnect.com></a> wrote: Why does du generate writes? Is this normal? </pre> </blockquote> <pre wrap=""> If you've L2ARC, it'd make sense that du (a program that traverses tons of directories if not more to find out how many blocks and/or bytes each file holds) would change the usage patterns AND that it would get cached in your L2ARC device. Caches are written when usage patterns change. So yes, it's expected behavior: caches change based on usage patterns, and "du -sh *" changes your usage to "read every directory". Hope this helps, Dan </pre> </blockquote> </body> </html>