Dump is used, when a system crashes to "dump" the actual system state to disk, so that postmortem analysis can be performed... :-)
Von meinem iPhone gesendet Am 17.09.2012 um 20:08 schrieb Andrew Haycock <[email protected]>: > Dan, that helped a lot more at least to the point that any further > questions are quite reasonably discoverable with experimentation or at > least google fodder. > > Well, I lie, there are a couple of questions but I don't think they're > too taxing. My concern with the ZIL being located on the SSD was not > speed, but drive wear. If ZIL is written too a lot is a 4GB partition > enough? Would an i-RAM solution be better? > > I think I will setup an L2ARC for my usage model, I reckon at the very > least it won't hurt any and I find the idea of these zones most > interesting especially for the Minecraft server. I may experiment with > the firewall side of things also. > > Also what is the dump used for exactly if it is not a swap? > > Thanks for the clarification, it's definitely helped an awful lot. > > > On 17 September 2012 18:53, Dan McDonald <[email protected]> wrote: >> Ooops, I needed to clarify something... >> >> On Mon, Sep 17, 2012 at 06:26:12PM +0100, Andrew Haycock wrote: >> >> <SNIP!> >> >>> When Dan explained his setup, he brought to my attention his 64GB root >>> disk. Aha! I think, this is something I was considering, but then I >>> come away thoroughly confused as I try to understand what his 52GB >>> rpool is used for (and indeed, what is rpool?), wonder at the 4GB >>> swap/dump (when using Linux I deliberately move the swap to a >>> mechanical drive to reduce wear on the SSD) and became utterly >>> perplexed as to how a 4GB ZIL qualifies as over-provisioned on an SSD >>> (I thought that ZIL was a log device and therefore written to a lot, I >>> had considered buying a Gigabyte i-RAM from the States to server this >>> role). Also Dan, do you use an L2ARC at all, could an SSD be >>> worthwhile for this? >> >> Okay, I made a mistake. 4GB isn't swap, just dump. >> >> ZFS has two abstractions: The pool, and the filesystem. >> >> A pool is comprised of one or more disk slices or one or more disks. Due to >> the Illumos grub's inability to boot from EFI volumes, you must slice your >> root disk into traditional Solaris/Illumos partitions. >> >> My root ZFS pool is the 52GB partition on my ssd: >> >> (1)# zpool status rpool >> pool: rpool >> <SNIP!> >> config: >> >> NAME STATE READ WRITE CKSUM >> rpool ONLINE 0 0 0 >> c4t1d0s0 ONLINE 0 0 0 >> >> errors: No known data errors >> (0)# >> >> My data pool ("tank") is comprised of two whole 2TB disks, plus the 4GB slice >> of SSD for slog: >> >> (0)# zpool status tank >> pool: tank >> <SNIP!> >> config: >> >> NAME STATE READ WRITE CKSUM >> tank ONLINE 0 0 0 >> mirror-0 ONLINE 0 0 0 >> c3t1d0 ONLINE 0 0 0 >> c5t3d0 ONLINE 0 0 0 >> logs >> c4t1d0s4 ONLINE 0 0 0 >> >> errors: No known data errors >> (0)# >> >> On a pool is one or more filesystems. Let's look at rpool: >> >> (1)# zfs list -r rpool >> NAME USED AVAIL REFER MOUNTPOINT >> <edited for content...> >> rpool 15.4G 35.3G 45K /rpool >> rpool/ROOT 10.6G 35.3G 31K legacy >> rpool/ROOT/oi_151a4 9.75M 35.3G 9.28G / >> rpool/ROOT/oi_151a6 10.6G 35.3G 9.34G / >> rpool/local 440M 35.3G 440M /usr/local >> rpool/zones 2.40G 35.3G 35K /zones >> rpool/zones/nexenta 714M 35.3G 33K /zones/nexenta >> rpool/zones/nexenta/ROOT 714M 35.3G 31K legacy >> rpool/zones/nexenta/ROOT/zbe 714M 35.3G 714M legacy >> rpool/zones/router 995M 35.3G 33K /zones/router >> rpool/zones/router/ROOT 995M 35.3G 31K legacy >> rpool/zones/router/ROOT/zbe-5 797K 35.3G 984M legacy >> rpool/zones/router/ROOT/zbe-6 994M 35.3G 984M legacy >> rpool/zones/webserver 744M 35.3G 33K /zones/webserver >> rpool/zones/webserver/ROOT 744M 35.3G 31K legacy >> rpool/zones/webserver/ROOT/zbe-5 971K 35.3G 734M legacy >> rpool/zones/webserver/ROOT/zbe-6 743M 35.3G 734M legacy >> (0)# >> >> You create a filesystem on a pool, and then it gets mounted somewhere. >> >> ZIL is written to a lot, but given my 2TB disks are 5900 RPM disks, even a >> stock SSD is faster. I personally do not use L2ARC, given most of my home >> server's filesystem usages is for backups, and at-most 35Mbit/sec web >> connections will be more network bound than disk-bound anyway (assuming no >> less than 10ms packet RTT, which is generous at a minimum). >> >>> I did find the zones a little confusing too, but as I plan on setting >>> up a virtual machine to practise on I'm sure I'll fathom things out >>> soon enough. >> >> Zones are lighter-weight VMs. You can give a zone its own TCP/IP stack, >> which is what I do. They share kernels with other zones. Setup and teardown >> of a zone is much quicker than a full-blown VM. >> >> Hope this helps some more, >> Dan >> >> >> ------------------------------------------- >> illumos-discuss >> Archives: https://www.listbox.com/member/archive/182180/=now >> RSS Feed: https://www.listbox.com/member/archive/rss/182180/23225516-9d3e32c1 >> Modify Your Subscription: https://www.listbox.com/member/?&; >> Powered by Listbox: http://www.listbox.com > > > ------------------------------------------- > illumos-discuss > Archives: https://www.listbox.com/member/archive/182180/=now > RSS Feed: https://www.listbox.com/member/archive/rss/182180/21175670-15e8c2c3 > Modify Your Subscription: https://www.listbox.com/member/?&; > Powered by Listbox: http://www.listbox.com > ------------------------------------------- illumos-discuss Archives: https://www.listbox.com/member/archive/182180/=now RSS Feed: https://www.listbox.com/member/archive/rss/182180/21175430-2e6923be Modify Your Subscription: https://www.listbox.com/member/?member_id=21175430&id_secret=21175430-6a77cda4 Powered by Listbox: http://www.listbox.com
