Hi managers,
The DS20E server (1GB RAM, 2CPUs, Tru64v5.1B) that we look after is short on
memory 
and the customer wants to add 3GB RAM (to have 4GB total). At the moment the
server 
has 3GB swap space, so we should probably increase that as well.
As far as we know, the recommended swap size for Tru64 is 2.5-3 * RAM if the
swap 
allocation mode is 'eager' and at least 1*RAM if the swap mode is 'lazy'. Is
it 
a problem if the system has more RAM than swap space (if we leave the swap
space 
size at 3GB and have 4GB RAM)? If that is not going to cause any problems,
we would 
probably wait for some time and monitor swap usage to see if they really
need more 
swap space on that server.
Increasing swap space size could be quite complicated here. What worries us
is 
that the server has 4*72GB disks all in one RAID 1+0 (the system was
originally 
configured by HP). Here is the output of the disklabel command:
8 partitions:
#            size       offset    fstype  fsize  bsize   cpg  # ~Cyl values
  a:      2097152            0     AdvFS                      #      0 - 511
  b:      6588334      2097152      swap                      #    512 -
2120*
  c:    284524544            0    unused      0      0        #      0 -
69463
  d:     94317226      1572864    unused      0      0        #    384 -
23410*
  e:     94317226     95890090    unused      0      0        #  23410*-
46437*
  f:      2695515    281829029     AdvFS                      #  68805*-
69463
  g:     11979980    269849049     AdvFS                      #  65881*-
68805*
  h:    261163563      8685486     AdvFS                      #   2120*-
65881*
where partition a is 'root_domain', b is swap, f is 'tmp_domain', g is
'usr_domain' 
and h is 'app01_domain'.
Our idea was to take some space from the h partition and either add it to
partition b
(if possible), or to make one of the unused partitions (d or e) as another
swap 
partition using that extra space from partition h. That would include the
following 
steps:
- make full filesystem backup
- save current disklabel (disklabel -r dsk0 > /tmp/dsk0label)
- unmount filesystems in app01_domain and remove that file domain
- edit /tmp/dsk0label - shrink partition h and extend partition b (if
possible) 
                        or create new swap partition using d or e.
- create a new disk label for dsk0 (disklabel -R dsk0 /tmp/dsk0label)
- create app01_domain and filesets, mount filesystems in app01_domain 
- restore data to the filesystems in app01_domain
QUESTIONS:
- is this procedure OK?
- can we be sure that if we are changing only partitions b and h nothing
else would
  be affected by the 'disklabel -R' command (especially not the
root_domain!!!)? 
- can the partition b be increased while it is in use 
  (or should it be done in single user mode)?
- is it better to create new swap partition, rather than to resize partition
b
  (it shouldn't cause performance problems as it's all striped anyway)?
- do we need to specify -r and -t options with 'disklabel -R' command to
make
  sure that the disk will be bootable (although it already is)?
- what do we need to change in the /etc/fstab and /etc/sysconfigtab if we
create 
  a new swap partition?
- is it a problem to have more RAM than swap space (e.g. in case the
application
  reserves the same amount of swap space as the real memory, or for memory
dump)?
- any other suggestions?
Thanks in advance,
Zoran
Received on Wed Nov 19 2003 - 22:50:05 NZDT