>Subject: Re: [linuxppc-release] [PATCH 1/2] powerpc, e5500: add networking >to defconfig > >On Thu, 12 May 2011 10:31:08 -0500 >Scott Wood <scottw...@freescale.com> wrote: > >> On Thu, 12 May 2011 01:11:03 -0500 >> Li Yang-R58472 <r58...@freescale.com> wrote: >> >> > >diff --git a/arch/powerpc/configs/e55xx_smp_defconfig >> > >b/arch/powerpc/configs/e55xx_smp_defconfig >> > >index 9fa1613..f4c5780 100644 >> > >--- a/arch/powerpc/configs/e55xx_smp_defconfig >> > >+++ b/arch/powerpc/configs/e55xx_smp_defconfig >> > >@@ -6,10 +6,10 @@ CONFIG_NR_CPUS=2 >> > > CONFIG_EXPERIMENTAL=y >> > > CONFIG_SYSVIPC=y >> > > CONFIG_BSD_PROCESS_ACCT=y >> > >+CONFIG_SPARSE_IRQ=y >> > >> > Hi Scott, >> > >> > I remember in previous testing that this option has a negative effect >on performance. Do we really need it to be enabled? >> >> I didn't change this setting, it just moved due to running it through >> savedefconfig. > >What was the performance impact?
It adds CPU cycles to the interrupt handling path. Will cause performance drop for benchmarks with large amount of interrupts such as IP forwarding. - Leo _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
