From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from majordomo by infradead.org with local (Exim 3.03 #1) id 13H4ce-0008TG-00 for mtd-list@infradead.org; Tue, 25 Jul 2000 14:19:48 +0100 Received: from dns.cygnus.co.uk ([194.130.39.3] helo=pasanda.cygnus.co.uk) by infradead.org with smtp (Exim 3.03 #1) id 13H4cc-0008TA-00 for mtd@infradead.org; Tue, 25 Jul 2000 14:19:46 +0100 From: David Woodhouse In-Reply-To: References: To: Bjorn Wesen Cc: Finn Hakansson , "mtd@infradead.org" , jffs-dev@axis.com Subject: Re: jffs_file_write Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Tue, 25 Jul 2000 14:19:44 +0100 Message-ID: <26128.964531184@cygnus.co.uk> Sender: owner-mtd@infradead.org List-ID: bjornw@axis.com said: > It usually takes about 1-2 seconds to erase a sector, so if you > really need to erase the entire 16 mb flash during GC, that's 250 > sectors times 2 seconds, about 8 minutes. Mileage may vary depending > on flash manufacturer - I've never used 16 mbyte flashes in anything.. > On these chips, erases only take a second. At the time, it was also 128 microseconds per _word_ write. So although a complete erase only takes 128 seconds, writing the whole device was more like 20 minutes. Even so, it should be far less than the 90 minutes that I observed. Is it possible that the GC was compacting the data on the flash repeatedly, before it had completed removing all the files? The command I was running was: rm -r /mnt/usr If it removed a couple of MB, then garbage collected, then removed another couple of MB, then would it have ended up moving the same data twice? -- dwmw2 To unsubscribe, send "unsubscribe mtd" to majordomo@infradead.org