Rao Shoaib writes: > > > Sure I am ccing NFS discuss so that they can look into this again if > they are not already. It will be interesting to know if there is extra
I'm not on that list, so my mail to them will likely bounce.. :( > over head in doing user to kernel copy than just kernel to kernel copy My understanding is that copyin is just bcopy with an on-fault handler to handle any potential page faults rather than taking a kernel trap. So, for a bulk data copy where all pages are present, it is essentially bcopy. > (which will be the FS case). BTW as you may know sendfile does not > always uses zero copy. I am assuming in your measurements it was using > zero copy. Yes. I spent quite a while cursing while I hacked on my test program to make sendfile do zero-copy. Thank goodness Solaris is open source, else it might have taken me much longer to figure out. Drew _______________________________________________ networking-discuss mailing list [email protected]
