Path: ...!3.eu.feeder.erje.net!feeder.erje.net!news2.arglkargh.de!news.mixmin.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: =?UTF-8?Q?Bj=C3=B6rn_Lundin?= Newsgroups: comp.sys.raspberry-pi Subject: Re: Move bookworm system from SSD to NVME Date: Sat, 3 Aug 2024 13:54:33 +0200 Organization: A noiseless patient Spider Lines: 22 Message-ID: References: <20240801171000.46ce321a2dd0cb03be7cba00@eircom.net> <20240801192923.a827ba8d22853e9bc6c5cfb3@eircom.net> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Sat, 03 Aug 2024 13:54:33 +0200 (CEST) Injection-Info: dont-email.me; posting-host="efc9bd2175bdf72bae3e59ba945183ed"; logging-data="3615632"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+HZDjCoMU8rNjBuXNwTSI7" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:bGivImpLlB5djVwyCtIDkDv14bY= Content-Language: en-US In-Reply-To: Bytes: 2344 On 2024-08-03 03:27, Lawrence D'Oliveiro wrote: > On Fri, 2 Aug 2024 15:12:57 +0100, The Natural Philosopher wrote: > >> SSDS/NVM have their own internal caching. > > True for all drives, unfortunately. > > It’s bloody stupid, because the drive caching is on the wrong side of the > drive interface. Better to leave it to the OS, which can use main RAM for > its filesystem caching, on the fast side of that drive interface. > > When a drive says to the OS driver “write is done”, it should mean “write > has gone to actual persistent storage”, not “write is in my cache”. I think they cause grief in the postgres mail lists some 15-20 years ago. They were called 'lying IDE-disks' and were not popular in that crowd. -- /Björn