From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <urs@isnogud.escape.de>
Subject: Re: [linux-lvm] LVM and *bad* performance (no striping)
References: <Pine.LNX.4.33.0102261839460.5502-100000@duckman.distro.conectiva>
From: Urs Thuermann <urs@isnogud.escape.de>
Date: 27 Feb 2001 11:33:23 +0100
In-Reply-To: <Pine.LNX.4.33.0102261839460.5502-100000@duckman.distro.conectiva>; from Rik van Riel on Mon, 26 Feb 2001 18:41:37 -0300 (BRST)
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Rik van Riel <riel@conectiva.com.br> writes:

> Maybe dd is reading in 512 byte blocks on /dev/sda5 and
> 4096 bytes on /dev/vg0/test ?

I've checked it.  The man page says if no bs is given, dd defaults to
512 bytes on any device.  I've also checked it with dd|wc.

The performance numbers I've observed seem to dependant on caching.


urs