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From: Richard Miller <9fans@hamnavoe.com>
To: 9fans@9fans.net
Subject: Re: [9fans] What does your fileserver consist of?
Date: Wed, 12 Oct 2016 10:48:53 +0100	[thread overview]
Message-ID: <f7bfedcb5ab248bbd43879113167404b@hamnavoe.com> (raw)
In-Reply-To: <CAPd04b4MPq10Z9CZOFfyT9ja_hRd_yc4mkOJ75puYgyeDNJW8Q@mail.gmail.com>

> I was wondering whether or not it'd be feasible to hook up something
> like http://tinyurl.com/jgov5gc (Amazon.com) to something small like a
> Raspberry Pi 3, or if the I/O would be too much for that kind of
> computer to handle.

Probably feasible but it is likely to be slow, because Plan 9's usb
implementation is not particularly efficient, and the pi's usb host
adapter hardware is especially bad.  Someone with a usb disk might
be able to quote actual bandwidth numbers.

I have a Seagate 1TB usb drive (SSD), which does not work at all with
Plan 9.  Haven't looked into it deeply, but it appears usb/disk isn't
parsing the usb interface descriptors correctly.

  ep7.0 storage csp 0x500608 csp 0x620608 vid 0x0bc2 did 0x231a Seagate Expansion dwcotg

There are two interfaces, and instead of selecting the correct one
(0x500608) usb/disk seems to be mixing up the endpoints from both
interfaces together:
	Seagate Expansion NA82688P
	conf: cval 1 attrib 80 500 mA
		iface csp storage.6.98
		  alt 0 attr 2 ival 0
		  alt 1 attr 2 ival 0
		  ep id 1 addr 1 dir inout type bulk itype 0 maxpkt 512 ntds 1
		  ep id 2 addr 130 dir inout type bulk itype 0 maxpkt 512 ntds 1
		  ep id 1 addr 1 dir inout type bulk itype 0 maxpkt 512 ntds 1
		  ep id 2 addr 130 dir inout type bulk itype 0 maxpkt 512 ntds 1
		  ep id 3 addr 131 dir in type bulk itype 0 maxpkt 512 ntds 1
		  ep id 4 addr 4 dir out type bulk itype 0 maxpkt 512 ntds 1
		dev desc 24[4]:  04 24 01 00
		dev desc 24[4]:  04 24 02 00
		dev desc 24[4]:  04 24 03 00
		dev desc 24[4]:  04 24 04 00

My file server is built from an intel atom mini-itx board with a SATA
disk.  Sequential read speed is over 100 MB/sec, more than enough to
saturate my network.  By comparison, I get less than 10 MB/sec reading
from a usb flash drive on the same machine.




  parent reply	other threads:[~2016-10-12  9:48 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-10-12  0:33 James A. Robinson
2016-10-12  5:27 ` Tyga
2016-10-12  9:20   ` Sergey Zhilkin
2016-10-12  9:22     ` Sergey Zhilkin
2016-10-12  9:48 ` Richard Miller [this message]
2016-10-12 14:46 ` Steven Stallion
2016-10-12 15:31 ` California Electric
2016-10-12 18:13   ` Steve Simon
2016-10-12 18:26 ` Brantley Coile
2016-10-12 22:38   ` James A. Robinson
2016-10-12 22:39     ` Brantley Coile
2016-10-12 23:19       ` Jules Merit
2016-10-13 15:54       ` James A. Robinson
2016-10-22 18:21         ` James A. Robinson
2016-10-22 21:06           ` Steven Stallion
2016-10-22 21:40             ` Steve Simon
2016-11-06 21:58               ` Tharaneedharan Vilwanathan
2016-11-10  5:21                 ` James A. Robinson
2016-11-10  5:41                   ` Tharaneedharan Vilwanathan

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