My Humax Forum » Freeview HD » HDR FOX T2

Reserved disk space

(13 posts)
  1. User has not uploaded an avatar

    Martin Liddle

    special member
    Joined: Feb '11
    Posts: 3,689

    offline

    Prompted by a question on DigitalSpy, I have checked the reserved disk space on my 1TB HDR-T2 and it is currently showing as 114GB which seems large. What is it used for?

    | Thu 24 Feb 2011 12:42:24 #1 |
  2. User has not uploaded an avatar

    raydon

    special member
    Joined: Feb '11
    Posts: 159

    offline

    Hi Martin,
    I've done a little research on this subject, so here's what I've been able to dig up so far.

    For a start, the whole issue of actual disk size has been clouded by a clever sales ploy used by HDD manufacturers.
    In software terms one kilobyte is equal to 1024 bytes.
    In hardware terms (as used by HDD manufacturers) one kilobyte equals only 1000 bytes.

    So for one gigabyte
    Binary = 1,073,741,824
    Decimal = 1,000,000,000
    Difference = 73,741,824
    or 6.8677% less !

    For a drive with stated capacity of 500GB you really get only 465.66GB.

    For one terabyte it gets even worse
    Binary = 1,099,511,627,776
    Decimal = 1,000,000,000,000
    Difference = 99,511,627,776
    or 9.095% less !

    For a drive with stated capacity of 1000GB you really get only 909.05GB.

    Looking under the bonnet of my 500Gb HDR T2 the Linux OS reports the file system partitions as follows:

    Filesystem Size Used Available Use% Mounted on
    /dev/sda1 1011.4M 35.4M 924.7M 4% /mnt/hd1
    /dev/sda2 447.6G 66.3G 358.6G 16% /mnt/hd2
    /dev/sda3 9.8G 261.2M 9.1G 3% /mnt/hd3

    However, From the T2's System Menu the disk space is reported like this:
    Available 373.6 Gb
    Used 74.0 Gb
    Reserved 72.7 Gb

    You can see that 'Available' plus 'Used' space totals 447.6Gb
    This ties in nicely with what Linux says is the partition size of hd2.
    Partition hd1 is 1Gb and is used for EPG data.
    Partition hd2 is the main media storage area for recordings. It also contains the 13.5Gb live buffer file.
    Partition hd3 is 9.8Gb and is used, as far as I can tell, as a cache for Portal content.

    Just where Humax get the figure of 72.7Gb Reserved I have no idea.
    What I do know is that it has no bearing whatsoever on the truth.

    | Sat 26 Feb 2011 17:12:05 #2 |
  3. grahamlthompson

    grahamlthompson

    special member
    Joined: Feb '11
    Posts: 14,442

    offline

    Raydon a bit off topic but can you clear up a point of confusion.

    Is it GB or Gb. I ask because b normally seems to mean bit rather than byte as in bps (bits/sec). Same confusion with respect to mbps or is it Mbps.

    | Sat 26 Feb 2011 19:03:25 #3 |
  4. User has not uploaded an avatar

    Martin Liddle

    special member
    Joined: Feb '11
    Posts: 3,689

    offline

    This Wikipedia article uses gigabyte (with abbreviation GB) as 10^9 and gigibyte (with abbreviation GiB) as 2^30 and I think I am happy with that convention.

    Thanks for the explanation on the disk usage.

    | Sat 26 Feb 2011 19:42:06 #4 |
  5. User has not uploaded an avatar

    raydon

    special member
    Joined: Feb '11
    Posts: 159

    offline

    grahamlthompson - 44 minutes ago  » 
    Raydon a bit off topic but can you clear up a point of confusion.
    Is it GB or Gb. I ask because b normally seems to mean bit rather than byte as in bps (bits/sec). Same confusion with respect to mbps or is it Mbps.

    In the context of my post all references in to bytes (I don't think I've ever seen HDD disk capacity referenced in bits. But you're right, Bytes should be capital with a B. Please forgive my sloppy syntax

    | Sat 26 Feb 2011 19:50:50 #5 |
  6. aldaweb

    aldaweb

    administrator
    Joined: Feb '11
    Posts: 400

    offline

    grahamlthompson - 1 hour ago  »  Same confusion with respect to mbps or is it Mbps.

    lower case m usually denotes one thousandth (10^-3) whereas capital M is a Million (10^6) so mbps would be like splitting the atom

    | Sat 26 Feb 2011 20:10:18 #6 |
  7. grahamlthompson

    grahamlthompson

    special member
    Joined: Feb '11
    Posts: 14,442

    offline

    raydon - 3 hours ago  » 

    grahamlthompson - 44 minutes ago  » 
    Raydon a bit off topic but can you clear up a point of confusion.
    Is it GB or Gb. I ask because b normally seems to mean bit rather than byte as in bps (bits/sec). Same confusion with respect to mbps or is it Mbps.

    In the context of my post all references in to bytes (I don't think I've ever seen HDD disk capacity referenced in bits. But you're right, Bytes should be capital with a B. Please forgive my sloppy syntax

    Please don't apologise I was sincerely confused. You see both around. As you must know I come from a heavy engineering background largely involving TW. or GW ( I hope that's right :-)). In future I will use B for Byte and b for bit

    | Sat 26 Feb 2011 23:19:00 #7 |
  8. User has not uploaded an avatar

    raydon

    special member
    Joined: Feb '11
    Posts: 159

    offline

    grahamlthompson - 1 hour ago  » 

    raydon - 3 hours ago  » 

    grahamlthompson - 44 minutes ago  » 
    Raydon a bit off topic but can you clear up a point of confusion.
    Is it GB or Gb. I ask because b normally seems to mean bit rather than byte as in bps (bits/sec). Same confusion with respect to mbps or is it Mbps.

    In the context of my post all references in to bytes (I don't think I've ever seen HDD disk capacity referenced in bits. But you're right, Bytes should be capital with a B. Please forgive my sloppy syntax

    Please don't apologise I was sincerely confused. You see both around. As you must know I come from a heavy engineering background largely involving TW. or GW ( I hope that's right :-)). In future I will use B for Byte and b for bit

    Graham, I don't believe for one minute you were confused. You were being pedantic for whatever reason I don't care to imagine. I will edit the original post to clarify your confusion but I believe most readers will be able to interpret the original post without any clarification whatsoever.

    | Sun 27 Feb 2011 0:44:53 #8 |
  9. grahamlthompson

    grahamlthompson

    special member
    Joined: Feb '11
    Posts: 14,442

    offline

    I was being absolutely honest. If you look back at many of my posts you will find GB and Gb used randomly. Gb also seems to be used more often than GB even in specification listings. Thanks for the clarification I was not intending to infer that the post was in in any way confusing, quite the reverse in fact.

    | Sun 27 Feb 2011 10:50:12 #9 |
  10. User has not uploaded an avatar

    raydon

    special member
    Joined: Feb '11
    Posts: 159

    offline

    O.K. thanks for clearing that up Graham. It seems though that I'm now unable to edit my original post.
    Admins, is this lack of an edit facility intentional, or is the edit button just hidden in some obscure place. My eyesight is not as good as it used to be.

    Hmmm. I can edit this post O.K. Is there a time limit on editing older posts ?

    | Sun 27 Feb 2011 13:05:17 #10 |

RSS feed for this topic

Reply »

You must log in to post.