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In this case the pages should have 12 pages in it, i.e. be 48K in size. Then the first 4 pages (16k, the first pagemap entry) would be read from image and put at address 0x1000000 thus occupying space up to the <code>0x1000000 + 4 * 4096 = 0x1004000</code> address. The last 8 pages (32k, the 2nd pagemap entry) would be read and put at the 0xCF000000 address.
In this case the pages should have 12 pages in it, i.e. be 48K in size. Then the first 4 pages (16k, the first pagemap entry) would be read from image and put at address 0x1000000 thus occupying space up to the <code>0x1000000 + 4 * 4096 = 0x1004000</code> address. The last 8 pages (32k, the 2nd pagemap entry) would be read and put at the 0xCF000000 address.
== Stacked images ==
When [[incremental dumps]] are performed, for every iteration a <code>parent</code> symlink is created, and images become dependent on their respective parent(s).
There appears the 3rd field in the pagemap, called <code>in_parent</code>. It is a boolean flag, when set, means the respective data for the given pagemap is available from a parent image. While searching for data in parent, the same algorithm is used -- first the pagemap is resolved, then the data is found in pages. For parent images, the data (either complete or partial) can also be found in ''its'' parent images.
Naturally, the bottom image (the one with no parent link) must have no <code>in_parent</code> bits set.
=== Example ===
Consider we have a pagemap from the previous example with <code>in_parent</code> bit set for one entry:
<pre>
{ 0x1000000, 4, in_parent }
{ 0xCF000000, 8 }
</pre>
In this case, the pages image would be only 32k in size, since the first 4 pages are to be found in the parent. Thus the parent pagemap image should container one or more pagemaps covering the <code>0x1000000 ... 0x1004000</code> area, for example, like this
<pre>
{ 0x1000000, 2 }
{ 0x1002000, 2, in_parent }
</pre>
This, in turn, means that the first 2 pages from this range are available from the parent pages image file, and the last 2 should be looked up deeper, i.e. in the grand-parent pagemaps.
== Deduplication ==
See [[Memory images deduplication]].
== See also ==
* [[Memory dumping and restoring]]
* [[Images]]
[[Category:Memory]]
[[Category:Memory]]
[[Category:Images]]
[[Category:Images]]
[[Category:Editor help needed]]