Arijit Das wrote:
I have RH3.0 installed in an AMD64 machine.
In this system, when I look at the virtual address space mappings of a process (say a sleep process), I find that almost 80% of its virtual address space has been taken by a private copy of /usr/lib/locale/locale-archive mapped to its virtual address space by default. Check this:
31396 KB r--p /usr/lib/locale/locale-archive
Only the pages of the file that are actually accessed are loaded into
physical memory. This mapping just reserves a slot of virtual memory
for those demand loaded pages to be mapped.
Total Virtual Memory = 38816 KB
On the other hand, when I look at the same info in a RH7.2 system, I see that a few small set of essential locale files have been mapped whose overall summed up size is around 236KB (way smaller than RH3.0)...Check this:
4 r--p /usr/lib/locale/en_US/LC_IDENTIFICATION
4 r--p /usr/lib/locale/en_US/LC_MEASUREMENT
4 r--p /usr/lib/locale/en_US/LC_TELEPHONE
4 r--p /usr/lib/locale/en_US/LC_ADDRESS
4 r--p /usr/lib/locale/en_US/LC_NAME
4 r--p /usr/lib/locale/en_US/LC_PAPER
4 r--p /usr/lib/locale/en_US/LC_MESSAGES/SYS_LC_MESSAGES
4 r--p /usr/lib/locale/en_US/LC_MONETARY
24 r--p /usr/lib/locale/en_US/LC_COLLATE
4 r--p /usr/lib/locale/en_US/LC_TIME
4 r--p /usr/lib/locale/en_US/LC_NUMERIC
172 r--p /usr/lib/locale/en_US/LC_CTYPE
This seems like a huge requirement of memory for each small process executed in the RH3.0 system and hence, shots up the memory requirement of the entire system because the mapped region /usr/lib/locale/locale-archive is privately mapped.
Private mapping means copy-on-write. But since these mappings are
read-only they will still be shared by other users of that file. So no
extra physical memory for each process mapping the file.
--
Brian Gerst
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
| |
 |