How to use new SSD and HDD drives most effectively

Started 2 months ago | Discussions thread
Tom_N Forum Pro • Posts: 18,522
Re: How to use new SSD and HDD drives most effectively

bmoag wrote:

It is indeed possible to move or backup the catalog as it is a file stored on a drive and as such can be copied or moved. The OP might contact On1 again.

The write speed of a mechanical drive is technically slower than an SSD but unless the file size is more than a few hundred mbs differences in write times are not perceptibly different compared to SSDs. Reading from a mechanical drive can be perceptibly slower, though not onerously so, for average sized files because of the longer random seek time. Moving large amounts of data on or off any mechanical drive can seem tortuous compared to SSD.

SSDs slaughter HDDs on random access performance.  This is why it can be useful to keep a Lightroom catalog file on a SSD, even when putting full-size photo files onto a HDD.

It is also why startup times are so much faster with SSDs than with HDDs.  Most OSes access a lot of files while booting up – data is laid out on disk in a fashion that may be good for modularity, but that does not optimize startup speed.  The sheer number of random accesses during startup gives SSDs a leg up over HDDs.

The other issue with mechanical drives is that the old distinction of platter speed indicting the drive is "faster" no longer holds true. The method used to access the platters can make a 7200 RPM drive crawl even slower when large file transfers are involved.

There's always been a distinction between RPM / maximum sequential transfer speed, and average random access time, with vendors tending to de-emphasize the latter.  But now there are "shingled magnetic recording" (SMR) drives that share one of the major disadvantages of flash memory:  you can't overwrite a small area without being forced to overwrite a bunch of other, unrelated areas.  SMR drives tend not to fare well in write speed tests, especially not in tests of how fast a RAID can bring a new mirrored drive up to speed after an old drive has died, and the user has done a drive swap.

Finding out which drives are CMR and which are SMR takes a bit of research, and there are some types of drives (especially bus-powered 2.5" notebook drives) where it can be almost impossible to avoid SMR.

Post (hide subjects) Posted by
MOD Austinian
MOD Austinian
MOD Austinian
MOD Austinian
MOD Austinian
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow