204 reputation
215
bio website identi.ca/grahamperrin
location United Kingdom
age 49
visits member for 3 years
seen Aug 9 at 20:54

Day job: IT support to CENTRIM and Brighton Business School – four days per week at Freeman Centre on University of Sussex campus, one day at Mithras House on University of Brighton campus.


Oct
7
comment Where is the central ZFS website now?
All services in the opensolaris.org domain became unavailable after 2013-03-24.
Apr
1
comment How to set finer-grain HDD Sleep settings in Mac OS 10.5?
It monitors sleep, wakeup and idleness of a Mac but (unless I'm missing something), SleepWatcher alone can not control sleep of a hard disk drive whilst the Mac is awake.
Jan
14
comment How to check that all ZFS snapshots within a pool are without holds before destroying that pool
In Super User: scripting to allow for white space (in the name of a ZFS dataset)
Dec
8
comment How to check that all ZFS snapshots within a pool are without holds before destroying that pool
Discussion of this question and its current answers in The Comms Room: chat.stackexchange.com/transcript/message/7189404#7189404
Nov
4
comment ZFS - how to partition SSD for ZIL or L2ARC use?
Elsewhere, in answer to a question in Ask Different – One mac, Two or more storage devices - how to divide things? – I added a section Multiple pools sharing a single SSD with reference to this answer. If you disagree with my guess about data integrity, which is focused on L2ARC (not on ZIL), I'll be pleased to receive a comment. Thanks.
Nov
3
comment For L2ARC and ZIL: is it better to have one large SSD for both, or two smaller SSDs?
For link purposes: a 2011 question from @ewwhite ZFS - how to partition SSD for ZIL or L2ARC use? and within the accepted answer, "… Dedicated ZIL and L2ARC devices per pool is the way to go".
Oct
18
comment Linux only seeing one disk of 4-disk eSATA enclosure
Is the eSATA device from the different manufacturer trouble-free on your two computers, Linux and Windows?
Oct
8
comment For L2ARC and ZIL: is it better to have one large SSD for both, or two smaller SSDs?
I added some background to the question. This answer seems ideal –thanks – I'll leave things open for a few days before accepting.
Oct
8
comment For L2ARC and ZIL: is it better to have one large SSD for both, or two smaller SSDs?
My current setup at home is far from kickass … maybe in the future. At work there's a bunch of kit that might be repurposed, but I don't have a date. Answers here (I like the first) help me to plan.
Oct
7
comment For L2ARC and ZIL: is it better to have one large SSD for both, or two smaller SSDs?
I see two current votes to close, instead can we simply move the question? Thanks @afrazier
Oct
7
comment Disk IO slow on ESXi, even slower on a VM (freeNAS + iSCSI)
Part of this answer might be good under a question that's currently in Super User: For L2ARC and ZIL: is it better to have one large SSD for both, or two smaller SSDs?.
Aug
18
comment Defragmenters useful for *nix?
If TN1150 (March 2004) is up-to-date, JHFS+ now is no different to JHFS+ then … however the more modern Systems seem to use the format in different ways. I plan to post an answer under Do Macs need to be defragmented? covering at least some of this. Meantime … rather than discuss in comments, let's aim for Ask Different Chat with the option of bookmarking.
Aug
18
comment Defragmenters useful for *nix?
It was an excellent article for its time, but the seven years since then have seen significant changes to preferred disk capacities, to uses of JHFS+, to uses of the attributes B-tree et cetera. The article does not consider fragmentation of attributes B-tree and (more commonly) catalog B-tree files; concerning the latter there's an answer to an Ask Different question relating to slowness of Time Machine. Considering modern use cases, I believe the 2004 conclusion is outdated.
Aug
18
comment Defragmenters useful for *nix?
The author begins with a note: "… sampled too few a volume to generalize my "results" …".
Aug
18
comment Defragmenters useful for *nix?
The 25 June 2009 edition of support.apple.com/kb/TS1417 is misleading. It mentions fragmentation in the context of fsck but fsck_hfs does not give information on fragmentation. Older versions of fsck_hfs have a strict requirement for contiguous free space for one type of rebuild; in other words: if free space is too fragmented, then rebuild is impossible. More recent versions of fsck_hfs are less demanding but still, it's sane to have plenty of contiguous free space.
Aug
18
comment Do I need to defrag MacOSX filesystems?
The gist of the answer "… you may benefit …" gets my vote up. The article referenced has been archived and is no longer updated by Apple. (February 2010 edition removed a reference to another archived article; it's otherwise no different from the June 2008 edition (crawled around that time) — not applicable to Snow Leopard Mac OS X 10.6 or Lion Mac OS X 10.7.
Aug
18
comment Do I need to defrag MacOSX filesystems?
The conclusion is reasonable based on results, but the author begins with a note: "… sampled too few a volume to generalize my "results" …".