Where can I hide defects?You can hide user area defects to P-list and G-list.
What is the difference between hiding defects into P-list or G-list ?Principal difference is that when you hide defect/group of defects into P-List defect disappear from translation (so capacity will less), in case of G-list defect replaced with sector from reserved area. Also you can’t hide tracks or group of tracks in G-list.
Also there will be delay in read/writing operations at replaced in G-list sectors – due to the fact that to read these sectors, the head must be moved to the reserve area and back, which takes quite a while.
What is the maximum amount of defects I can hide?Typically maximum length of G-list – 1024 entries (or 1912 sectors) and it depens on size of reserved area. On new foDefects can be only sectoral (so single LBA or LBA chain).
Maximum amount of chains for P-list depends on family. On old HDDs – 1022, on newer – 4094, on latest – 16382. You can check the exact value for a specific disk from “Zones and heads inactivation” startup log (“P-List capacity” parameter). Defects can be not only sectoral, you can hide single LBA, group of LBA till 24 sectors per track, whole tracks or group of tracks.
How to completely disable dead head?You need to use “Zone and heads inactivation” feature. Please note that such ability is available only for version greater than 6.0.x.
After that you will be asked how to apply HDD capacity and confirm recounting translator:
If you want to revert to a previous state before this procedure you need to write back CP 56 and DD which was automatically saved in ZoneBackup catalog of HDD profile.
How to hide zones?
Almost same way like disabling heads – you need to open microzones editor (Tools -> Utility extensions -> Zones and heads inactivation or Ctrl+Alt+3), select zones to hide and press “Apply table” icon.
There is some known restrictions.
It’s impossible to disable head if number of microzones per head < than P-list capacity. For example, the MK3263GSX model has 1022 entries in the P-List, but the number of microzones per each Head is 2196. Therefore, it is impossible to hide a dead head completely.
You can easily estimate possibility of hiding head: check number of zones by head then check P-list capacity. If P-list is smaller – it’s impossible.
For the 32GSX and 37GSX families, PBAs can be hidden only up to a certain limited number. For example, at MK6037GSX you can hide 17849743 PBA, but 17849744 and more can’t be hidden. Probably, this applies only to some f/w.
There are many families that don’t allow to hide PBA=0, probably only some f/w, it has to be checked experimentally. That’s why at such HDDs you won’t be able to completely hide the Head 0. To be more precise, it will be possible to hide all the PBAs related to Head 0, except PBA=0. If you faced with this situation, I recommend to try hide PBA=0 in G-list.
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