From owner-freebsd-usb@FreeBSD.ORG Tue Jun 17 10:16:08 2008 Return-Path: Delivered-To: usb@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 7BBCA1065671 for ; Tue, 17 Jun 2008 10:16:08 +0000 (UTC) (envelope-from jhs@berklix.org) Received: from flat.berklix.org (flat.berklix.org [83.236.223.115]) by mx1.freebsd.org (Postfix) with ESMTP id 0DB868FC18 for ; Tue, 17 Jun 2008 10:16:07 +0000 (UTC) (envelope-from jhs@berklix.org) Received: from js.berklix.net (p549A4F25.dip.t-dialin.net [84.154.79.37]) (authenticated bits=0) by flat.berklix.org (8.13.8/8.13.8) with ESMTP id m5H9aXPk034343 for ; Tue, 17 Jun 2008 11:36:34 +0200 (CEST) (envelope-from jhs@berklix.org) Received: from fire.js.berklix.net (fire.js.berklix.net [192.168.91.41]) by js.berklix.net (8.13.8/8.13.8) with ESMTP id m5H9aN6W028374 for ; Tue, 17 Jun 2008 11:36:23 +0200 (CEST) (envelope-from jhs@berklix.org) Received: from fire.js.berklix.net (localhost [127.0.0.1]) by fire.js.berklix.net (8.13.8/8.13.8) with ESMTP id m5H9aIJn085539 for ; Tue, 17 Jun 2008 11:36:23 +0200 (CEST) (envelope-from jhs@fire.js.berklix.net) Message-Id: <200806170936.m5H9aIJn085539@fire.js.berklix.net> To: usb@freebsd.org From: "Julian Stacey" Organization: http://berklix.com BSD Linux Unix Consultancy, Munich Germany. User-agent: EXMH on FreeBSD http://berklix.com/free/ X-URL: http://berklix.com/~jhs/cv/ Date: Tue, 17 Jun 2008 11:36:18 +0200 Sender: jhs@berklix.org Cc: Subject: best block size for file systems on USB media ? X-BeenThere: freebsd-usb@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: FreeBSD support for USB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 17 Jun 2008 10:16:08 -0000 Hi usb@freebsd.org Do USB flash memory sticks have cache ram ? What are best file system block sizes to write USB media (to maximise access speed) ? Any URLS to RTFM welcome ;-) I'm using mine to back up my personal tree of private data, (mail & tech notes & sources etc, lots of smallish files), I'm using /usr/ports/net/rdist6 to backup. My biggest stick, a 2G Sandisk Cruzer micro (vendor 0x0781 product 0x5151) is awfully slow (much slower per Meg than other manufacturers smaller sticks) (& other 2G Sandisk sticks bought in same purchase from same vendor are also awfully slow on Win-XP, so maybe these have less or no cache ram (if such things have cache at all ?) or maybe they were a fraudulent batch without cache when they should have had cache or ... ? ) Maybe some other sticks work on different block size ? Maybe for many of my small files, the stick needs to read a big block, before modifying a small chunk & writing back to block ? Block sizes was a question I'd meant to ask earlier, just for normal sticks with a normal FreeBSD FS on there, now it's become even more of an interest, using a BSD FS within an encrypted gbde partition ref. Read http://www.freebsd.org/doc/en/books/handbook/disks-encrypting.html which is slower still from encyption overhead (noticeable doing a reload into new empty FS). Some FS issues might be better discussed later on fs@freebsd.org, but first, what's known about USB hardware block sizes please ? Julian -- Julian Stacey: BSDUnixLinux C Prog Admin SysEng Consult Munich www.berklix.com Mail plain ASCII text. HTML & Base64 text are spam.