From mboxrd@z Thu Jan 1 00:00:00 1970 MIME-Version: 1.0 In-Reply-To: References: From: Steven Stallion Date: Wed, 19 Oct 2016 11:44:35 -0500 Message-ID: To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Content-Type: text/plain; charset=UTF-8 Subject: Re: [9fans] Fossil+Venti system memory requirements to be aware of? Topicbox-Message-UUID: a5f32e60-ead9-11e9-9d60-3106f5b1d025 Hi Jim, It probably helps to break apart fossil and venti for the sake of the conversation. While you can use fossil as a standalone filesystem, it is effectively your write cache in this scenario since it will be backed by venti. Conventional wisdom is to size your main fossil fs based on how much you plan to write in a given day. In my personal setup, I use a 32GB main fs, with the rest of a mirrored SSD pair dedicated to an "other" fossil partition where I place data that doesn't get backed up. Sizing venti is also simple. Start with something manageable; I chose 32GB at the time. Venti behaves much like a WORM with some additional deduplication (I'm glossing over gobs of detail here), so you'll likely need much less than you think. You can grow your venti story over time if you need, and it's also relatively trivial to move your data between stores. In short, start small and grow as needed. For reference, when I ran Coraid's fs based on 64-bit Ken's (WORM only, no dedupe) in RWC (based on the main fs in Athens). Over the course of a few years the entire WORM grew to around 35GB. This was for a couple dozen people working full time. I believe I had the LUN configured to something rather large at the time - around 12TB. All wasted space. HTH, Steve On Wed, Oct 19, 2016 at 3:41 AM, James A. Robinson wrote: > Anyone able to tell me whether or not there are > disk size limits I should beware of given a limited > amount of system memory in a file server? > > What I'm wanting to try and do is get a hardware > RAID1+0 enclosure and put in 20TB of disk (so > 10TB of usable space). > > The board I am looking at will take up to 8 gb of > system memory. Is that going to place any sort > of a limit on fossil+venti partition sizes? > > There are old threads that discuss a problem > with venti and the user hitting swap (the amount > of memory wasn't specified, at least not as > far as I could find in my archive or via google). > > > Jim >