Just to talk some stats here: We're talking about a difference of 20%, but that is still 364 MB/s more... You'd better have a beefy machine, as the 1990 MB/sec is more than 3 64-bit, 66 MHz PCI busses can transfer. The Seagate 15K RPM drives transfer about 40 MB/sec (peak), and you would need almost 50 of them, to reach 1990 MB/sec. Still, you would only need 3 ASR-3400S controllers to drive them, so I suppose it's not out of reach :-) I'd love to see such a machine ... Best regards, Mads Peter Bach ----- Original Message ----- From: "Andy Arvai" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, April 19, 2001 10:32 AM Subject: Re: raid5 checksumming speed > > Is there are way, short of hacking the kernel, to force it to use > p5_mmx? If the machine is a file server then this might be useful. > > Andy > > >From [EMAIL PROTECTED] Wed Apr 18 22:55 PDT 2001 > >Subject: Re: raid5 checksumming speed > >From: Gregory Leblanc <[EMAIL PROTECTED]> > >To: [EMAIL PROTECTED] > >Mime-Version: 1.0 > >X-Mailing-List: [EMAIL PROTECTED] > > > >On 18 Apr 2001 18:31:02 -0700, Andy Arvai wrote: > >> > >> I was looking at my system log file at the output from the raid drivers > >> and I noticed the following: > >> > >> raid0 personality registered > >> raid1 personality registered > >> raid5 personality registered > >> raid5: measuring checksumming speed > >> 8regs : 1342.400 MB/sec > >> 32regs : 906.400 MB/sec > >> pIII_sse : 1990.800 MB/sec > >> pII_mmx : 2214.000 MB/sec > >> p5_mmx : 2354.000 MB/sec > >> raid5: using function: pIII_sse (1990.800 MB/sec) > >> md driver 0.90.0 MAX_MD_DEVS=256, MD_SB_DISKS=27 > >> md.c: sizeof(mdp_super_t) = 4096 > >> > >> Why does the driver choose pIII_sse vs. the faster p5_mmx? - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to [EMAIL PROTECTED]
