On Fri, 19 Feb 2021 at 16:46, Semih Ozlem <semihozlemlinuxu...@gmail.com> wrote: > > Hello everyone, > > In comparing performance what are the pros and cons to using > > (i) live usb flash disk
Works, boots on anything (BIOS and UEFI), but you can't update and you can't readily save your data. Boot speed slow, because the OS is in a compressed disk image. > (ii) live usb with persistence on a flash disk Much the same as above. You can just save your data and settings, but updating is very inefficient as you can't rewrite the contents of the compressed disk image -- updated files go into your persistence volume. OK for emergency use, not for routine operation. > (iii) full installation on a flash disk I have done this and used such systems. If you want to use it on multiple different computers you may have issues -- e.g. the same bootable key may not boot both a BIOS PC and a UEFI PC. If there are OSes installed on the HDD as well, and you do an update, then those OSes will be added to the GRUB menu on the key, creating entries that won't work on any other PC. If you always use it on the same machine, it's acceptable. I had a company which sold such a bootable key for a while. It worked and the speed is quite reasonable... but when you run normally, it is writing settings to the key all the time. When you update, it writes a lot of data to the key. This wears out the flash memory on the key and in time the key will fail. If in daily use, it may well wear out in 6 months or so. And when flash memory wears out, it is not like a defective hard disk, which dies slowly and gives you a chance to recover your data... when flash wears out, one failed write might corrupt the volume and the whole disk stops working completely. I.e. you lose all your data. It works but it is only suitable for occasional or lightweight use. I wrote a how-to guide for building such a system; it is here: https://liam-on-linux.livejournal.com/50416.html It is a little dated now but still valid. It details some optimisations you can do to boost life -- such as using a filesystem without journalling, disabling access-time storage and things. These help but not much. I have a fileserver that boots off a USB key, but it has no GUI and is never normally used interactively. That works fine. Data is stored on a RAID of SATA drives. > (iv) full installation on an external hard disk (ssd or other) So long as your computer boots happily from it, works fine. The same caveats about about dual-booting and transportability mentioned above apply. Hard disks are a little slower than a USB 2 flash drive, but they don't wear out. A USB3 flash drive might well be a lot quicker than a hard disk, An internal SSD is much faster than a USB2 flash drive and a little quicker than a USB 3 external flash drive. > (v) full installation on an internal hard disk (ssd or other) This is the best and fastest. Linux does not use licence keys, activation or anything; a bootable HDD or SSD can be moved to another computer without problems. (With a few obvious limitations; e.g. a 64-bit install will not work on a 32-bit computer.) My recommendation is, have _both_ a small SSD and a big HDD. Install with / (the root partition) on the HDD, and /home (the home partition) and swap on the HDD. This gives you very fast boot times, very fast program loading, etc. -- but lots of space on a medium that won't wear out. User configuration files are relatively tiny and you will not notice any slow-down in performance from having them on a slower HDD compared to on a fast SDD. -- Liam Proven – Profile: https://about.me/liamproven Email: lpro...@cix.co.uk – gMail/gTalk/gHangouts: lpro...@gmail.com Twitter/Facebook/LinkedIn/Flickr: lproven – Skype: liamproven UK: +44 7939-087884 – ČR (+ WhatsApp/Telegram/Signal): +420 702 829 053
