On 9/19/19 10:51 PM, Trond Myklebust wrote:
I don't understand why klibc would default to supplying a timeo=7 argument at all. It would be MUCH better if it just let the kernel set the default, which in the case of TCP is timeo=600. I agree with your argument that replaying requests every 0.7 seconds is just going to cause congestion. TCP provides for reliable delivery of RPC messages to the server, which is why the kernel default is a full minute. So please ask the klibc developers to change libmount to let the kernel decide the default mount options. Their current setting is just plain wrong.
This was what I asked in my first message to their mailing list, https://lists.zytor.com/archives/klibc/2019-September/004234.html Then I realized that timeo=600 just hides the real problem, which is rsize=1M. NFS defaults: timeo=600,rsize=1M => lag nfsmount defaults: timeo=7,rsize=1MK => lag AND dmesg errors My proposal: timeo=whatever,rsize=32K => all fine If more benchmarks are needed from me to document the "NFS defaults: timeo=600,rsize=1M => lag" I can surely provide them. Thanks, Alkis
