====== Expanding secondary pool space ======
On busier systems with plenty of memory (my 11/83 has a full 4MB of PMI RAM), you may wish to allocate additional secondary pool space. The reasoning behind doing so is outside the scope of this document; you are highly encouraged to read "Chapter 8: Memory Management" in the [[http://bitsavers.org/pdf/dec/pdp11/rsx11m_plus/RSX11Mplus_V4.x/7/AA-JS14A-TC_RSX-11M_PLUS_V4.0_RSX-11M-PLUS_and_MicroRSX_System_Management_Guide_Sep87.pdf|RSX-11M-PLUS and Micro/RSX System Management Guide (pp.304)]] manual.

Expanding the secondary pool temporarily can be done in a few different ways, but doing so permanently requires a sysgen and VMR. First, temporarily; ''LOAD /EXP=SEC /SIZE=n'' can be used to increase the size of a given pool (in this example, the secondary pool as specified by ''/EXP=SEC'') by ''n'' words:

<code>
>LOAD /EXP=SEC /SIZE=100
</code>

You can also expand the size of the secondary pool at boot in the file ''LB:[1,2]SYSPARAM.DAT'', using the ''SECONDARY_POOL=n'' statement. This will increase the size of the pool by ''n'' 32-word blocks.

Finally, the recommended method of increasing secondary pool is via sysgen and VMR. First, you will need to generate a new system image:

<code>
>set def [200,200]
>@sysgen
</code>

Do not boot the new image yet. Create a new one with PIP, and make sure the ''/BL:'' flag does not exceed your amount of available system memory or things will break in strange and terrifying ways:

<code>
>set def [1,54]
>PIP RSX11M.SYS/CO/NV/BL:1026.=RSX11M.TSK
</code>

Next, edit ''SYSVMR.CMD'' and find the ''SET /PAR=SECPOL'' line- this is where your system's secondary pool is defined. On a system with a lot of memory you can comfortably set this to 10000. If you have limited resources you will want to start smaller, in increments of maybe 500-1000 at a time, monitoring available pool space and stability as you go.

Regardless, you will now need to re-VMR and boot the new image:

<code>
> vmr @sysvmr
[...]
POOL=1200:13640.:13640.:2004
>boo [1,54]
XDT: 87

XDT>g
RSX-11M-PLUS V4.6   BL87


>
 sav /wb/mou="/acp=unique/lru=14/win=30"
 [...]
 >set /secpol
 SECPOL=3833.:4096.:93%
</code>