# 1 G memory problem

## concord

Hi Friends:

I add more memory to my laptop from 512M. The total is 1G right now. But:

```
 cat /proc/meminfo

MemTotal:       903900 kB

MemFree:        144184 kB

Buffers:        149736 kB

Cached:         315580 kB

SwapCached:          0 kB

Active:         331496 kB

Inactive:       305892 kB

SwapTotal:     1052216 kB

SwapFree:      1052216 kB

Dirty:            5324 kB

Writeback:          32 kB

AnonPages:      172092 kB

Mapped:          66904 kB

Slab:           108648 kB

SReclaimable:    99276 kB

SUnreclaim:       9372 kB

PageTables:       2024 kB

NFS_Unstable:        0 kB

Bounce:              0 kB

CommitLimit:   1504164 kB

Committed_AS:   550200 kB

VmallocTotal:   122572 kB

VmallocUsed:     30448 kB

VmallocChunk:    87752 kB
```

Why? where is lost memory (about 100M)?

Thanks for help!

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## richard.scott

My guess is that you have shared memory with your graphics adapter.

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## concord

 *richard.scott wrote:*   

> My guess is that you have shared memory with your graphics adapter.

 

But if I boot the laptop with my generic USB HD gentoo. The amount is correct.

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## energyman76b

try google. This question has asked so many times it is boring to answer it.

Short: pci device space and other memory mapped stuff. 

Just google.

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## x22

Is it x86 (32bit)?

If yes, then enable 4GB memory (CONFIG_HIGHMEM4G) in kernel configuration. The 1GB option is actually only about 900MB.

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## concord

 *x22 wrote:*   

> Is it x86 (32bit)?
> 
> If yes, then enable 4GB memory (CONFIG_HIGHMEM4G) in kernel configuration. The 1GB option is actually only about 900MB.

 

Thanks very much! The arch=x86. I have re-make kernel with your suggestion. It works!

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## wesw02

I saw this issue happen when I first built my HTPC (amd64), at the time I didn't concern myself with it to much because I was adding another 1GB (so that I would have dual channel memory) the following week. After I added the 1GB my memory the missing 100MB returned, /proc/meminfo showed 2GB. 

(I know this is probably in no way helpful, but I still felt the need to mention it)

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