<html><body bgcolor="#FFFFFF"><div><div><span class="Apple-style-span" style="-webkit-tap-highlight-color: rgba(26, 26, 26, 0.296875); -webkit-composition-fill-color: rgba(175, 192, 227, 0.230469); -webkit-composition-frame-color: rgba(77, 128, 180, 0.230469); ">On Sep 15, 2009, at 9:37 PM, Eugene Vilensky <<a href="mailto:evilensky@gmail.com">evilensky@gmail.com</a>> wrote:</span><br></div></div><div><br></div><div></div><blockquote type="cite"><div><br><blockquote type="cite"><span>For those who have wondered why NFS on EL5 is slower than on EL4 I</span><br></blockquote><blockquote type="cite"><span>provide these links for your edification.</span><br></blockquote><blockquote type="cite"><span></span><br></blockquote><blockquote type="cite"><span><a href="http://kbase.redhat.com/faq/docs/DOC-15355">http://kbase.redhat.com/faq/docs/DOC-15355</a></span><br></blockquote><span></span><br><span></span><span class="Apple-style-span" style="color: rgb(0, 0, 0); -webkit-tap-highlight-color: rgba(26, 26, 26, 0.289062); -webkit-composition-fill-color: rgba(175, 192, 227, 0.222656); -webkit-composition-frame-color: rgba(77, 128, 180, 0.222656); ">This was introduced in 5.4 or 5.0 or somewhere between?</span></div></blockquote><br><span class="Apple-style-span" style="-webkit-tap-highlight-color: rgba(26, 26, 26, 0.296875); -webkit-composition-fill-color: rgba(175, 192, 227, 0.230469); -webkit-composition-frame-color: rgba(77, 128, 180, 0.230469); "><blockquote type="cite"><div><span></span></div></blockquote></span><div><span class="Apple-style-span" style="color: rgb(0, 35, 163);">The time based scheduling was introduced in 5.0.</span></div><div><span class="Apple-style-span" style="color: rgb(0, 35, 163);"><br></span></div><div><span class="Apple-style-span" style="color: rgb(0, 35, 163);">Honestly even the quantum based scheduling in 4.0 had performance problems with kernel based threads, just less obvious.<span class="Apple-style-span" style="-webkit-tap-highlight-color: rgba(26, 26, 26, 0.289062); -webkit-composition-fill-color: rgba(175, 192, 227, 0.222656); -webkit-composition-frame-color: rgba(77, 128, 180, 0.222656); "></span></span></div><div><span class="Apple-style-span" style="color: rgb(0, 35, 163); -webkit-tap-highlight-color: rgba(26, 26, 26, 0.285156); -webkit-composition-fill-color: rgba(175, 192, 227, 0.21875); -webkit-composition-frame-color: rgba(77, 128, 180, 0.21875);"><br></span></div><div><span class="Apple-style-span" style="color: rgb(0, 35, 163);"><span class="Apple-style-span" style="-webkit-tap-highlight-color: rgba(26, 26, 26, 0.289062); -webkit-composition-fill-color: rgba(175, 192, 227, 0.222656); -webkit-composition-frame-color: rgba(77, 128, 180, 0.222656); ">All kernel based IO should run under the same IO context, it doesn't make sense to have the kernel competing against itself. The only exception to that would be a RT kernel that might have a RT context that preempts even the kernel context.</span></span></div><div><span class="Apple-style-span" style="color: rgb(0, 35, 163); -webkit-tap-highlight-color: rgba(26, 26, 26, 0.285156); -webkit-composition-fill-color: rgba(175, 192, 227, 0.21875); -webkit-composition-frame-color: rgba(77, 128, 180, 0.21875);"><br></span></div><div><span class="Apple-style-span" style="color: rgb(0, 35, 163);"><span class="Apple-style-span" style="-webkit-tap-highlight-color: rgba(26, 26, 26, 0.289062); -webkit-composition-fill-color: rgba(175, 192, 227, 0.222656); -webkit-composition-frame-color: rgba(77, 128, 180, 0.222656); ">-Ross</span></span></div><div><span class="Apple-style-span" style="color: rgb(0, 35, 163);"><span class="Apple-style-span" style="-webkit-tap-highlight-color: rgba(26, 26, 26, 0.289062); -webkit-composition-fill-color: rgba(175, 192, 227, 0.222656); -webkit-composition-frame-color: rgba(77, 128, 180, 0.222656); "> </span></span></div></body></html>