Date: Tue, 15 Jan 2013 12:55:27 -0800 From: Adrian Chadd <adrian@freebsd.org> To: Karim Fodil-Lemelin <fodillemlinkarim@gmail.com> Cc: freebsd-hackers@freebsd.org Subject: Re: IBM blade server abysmal disk write performances Message-ID: <CAJ-VmomK2VvokDmZa1FsHqDs0xxA7UpQNGQBiqCLf8Jysw0_9g@mail.gmail.com> In-Reply-To: <50F5BC08.1060700@gmail.com> References: <CAA3ZYrACHLU-4OyhLdD%2BmfCDR_kubBg-AiVcopL-skqDurE7YA@mail.gmail.com> <50F5BC08.1060700@gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
Hi, You're only doing one IO at the end. That's just plain silly. There's all kinds of overhead that could show up, that would be amortized over doing many IOs. You should also realise that the raw disk IO on Linux is by default buffered, so you're hitting the buffer cache. The results aren't going to match, not unless you exhaust physical memory and start falling behind on disk IO. At that point you'll see what the fuss is about. Adrian
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAJ-VmomK2VvokDmZa1FsHqDs0xxA7UpQNGQBiqCLf8Jysw0_9g>