HPE 3PAR StoreServ Storage
1748159 Members
3934 Online
108758 Solutions
New Discussion

Re: 3PAR LDFree CPG

 
SOLVED
Go to solution
Ares7
Occasional Advisor

3PAR LDFree CPG

Hello. How to correctly calculate the size of free space on a CPG group if the system has different sizes of hard drives? The LDFree do not change for six month, but our DB continue to grow. I don't believe this parameter.
Work cli% showspace -cpg SSD_r5

 

----------------------(MiB)-----------------------
CPG -------EstFree------- -----------Efficiency------------
Name RawFree LDFree OPFree Base Snp Free Total Compact Dedup Compress DataReduce Overprov
SSD_r5 520192 390144 - 1321600 1536 1005440 2328576 1.37 - - - 0.58

 

 

8 REPLIES 8

Re: 3PAR LDFree CPG

@Ares7 

Many details missing but I am assuming you have only SSD drives in this system and one CPG where VVs got created.

LDFree is something which will come into use when all existing LD allocated space exausted. Any new space allocation 3PAR will do by taking space from LDFree or in case any other condition met for CPG growth.

In your case we can see Free space shows 1005440 MB which is approx 1000GB or 1TB of space. This should take care of space requirement actually. If you really want to freeup this space and want to see this space getting added to LDFree then run compactcpg on this SSD CPG.

Note: Better to run compactcpg when no other tune operation active. Also you need to monitor the compactcpg task and monitor for performance issues. If severe performance then cancel the task. Otherwise run compactcpg in out of office hours.

There are few commands if you want to crossverify space in CPG level,

showcpg -d
showcpg -r
showcpg -s
showsys -space

 

Hope this helps!
Regards
Subhajit

I am an HPE employee

If you feel this was helpful please click the KUDOS! thumb below!

************************************************************************

 


I work for HPE
Accept or Kudo
Ares7
Occasional Advisor

Re: 3PAR LDFree CPG

Thank you. What about mixed size drives? 1000 GB is a raw free space. I cannot use all free space of 920 Gb drives, because the system use only 480 Gb

i% showcage
Id Name  LoopA Pos.A LoopB Pos.B Drives Temp  RevA RevB Model FormFactor
 0 cage0 0:1:1     0 1:1:1     0     10 24-27 409b 409b DCN2  SFF
Work cli% showpd
                           ---Size(MiB)--- ----Ports----
Id CagePos Type RPM State    Total    Free A      B      Capacity(GB)
 0 0:0:0   SSD  100 normal  456704   72704 0:1:1* 1:1:1*          480
 1 0:1:0   SSD  100 normal  456704    4096 0:1:1* 1:1:1*          480
 2 0:2:0   SSD  100 normal  456704   62464 0:1:1* 1:1:1*          480
 3 0:3:0   SSD  100 normal  456704    7168 0:1:1* 1:1:1*          480
 4 0:4:0   SSD  100 normal  456704   76800 0:1:1* 1:1:1*          480
 5 0:5:0   SSD  100 normal  456704    9216 0:1:1* 1:1:1*          480
 6 0:6:0   SSD  100 normal  456704   75776 0:1:1* 1:1:1*          480
 7 0:7:0   SSD  100 normal  456704    2048 0:1:1* 1:1:1*          480
 8 0:8:0   SSD  150 normal  872448  435200 0:1:1* 1:1:1*          920
 9 0:9:0   SSD  150 normal  872448  359424 0:1:1* 1:1:1*          920
---------------------------------------------------------------------
10 total                   5398528 1104896

  

Ares7
Occasional Advisor

Re: 3PAR LDFree CPG

% showpd -c
                             -------- Normal Chunklets -------- ---- Spare Chunklets ----
                             - Used -- -------- Unused -------- - Used - ---- Unused ----
Id CagePos Type State  Total   OK Fail Free Uninit Unavail Fail OK  Fail Free Uninit Fail
 0 0:0:0   SSD  normal   446  302    0   71      0       0    0  0     0   73      0    0
 1 0:1:0   SSD  normal   446  370    0    4      0       0    0  0     0   72      0    0
 2 0:2:0   SSD  normal   446  313    0   61      0       0    0  0     0   72      0    0
 3 0:3:0   SSD  normal   446  367    0    7      0       0    0  0     0   72      0    0
 4 0:4:0   SSD  normal   446  299    0   75      0       0    0  0     0   72      0    0
 5 0:5:0   SSD  normal   446  365    0    9      0       0    0  0     0   72      0    0
 6 0:6:0   SSD  normal   446  300    0   74      0       0    0  0     0   72      0    0
 7 0:7:0   SSD  normal   446  372    0    2      0       0    0  0     0   72      0    0
 8 0:8:0   SSD  normal   852  289    0  425      0       0    0  0     0  138      0    0
 9 0:9:0   SSD  normal   852  364    0  351      0       0    0  0     0  137      0    0
-----------------------------------------------------------------------------------------
10 total                5272 3341    0 1079      0       0    0  0     0  852      0    0

Re: 3PAR LDFree CPG

@Ares7 

It will be difficult to comment without knowing your CPG defination. We need to understand RAID, HA and set size configured on the CPG.

You can provide below output,

showcpg -sdg

Mixing different size not a good practice. You can seperate drives with different size in different CPG as well.

 

Hope this helps!
Regards
Subhajit

I am an HPE employee

If you feel this was helpful please click the KUDOS! thumb below!

************************************************************************


I work for HPE
Accept or Kudo
Ares7
Occasional Advisor

Re: 3PAR LDFree CPG

% showcpg -sdg
          -----(MiB)-----
Id Name   Warn Limit Grow Args
 0 SSD_r1    -     - 8192 -ssz 2 -ha mag -t r1 -p -devtype SSD
 1 SSD_r5    -     - 8192 -ssz 4 -ha mag -t r5 -p -devtype SSD
 2 SSD_r6    -     - 8192 -ssz 8 -ha mag -t r6 -p -devtype SSD
Solution

Re: 3PAR LDFree CPG

@Ares7 

You are already with HA as mag so that will try to give you max space.

Few of your drives are with very less chunklet left so you should consider running compactcpg immediately and then do a tunesys if required to rebalance chunklets accross all drives.

 

Hope this helps!
Regards
Subhajit

I am an HPE employee

If you feel this was helpful please click the KUDOS! thumb below!

************************************************************************


I work for HPE
Accept or Kudo
Ares7
Occasional Advisor

Re: 3PAR LDFree CPG

Thank you! What does "-ha mag" mean?

Re: 3PAR LDFree CPG

@Ares7 

HA means High Availability

Mag means Magazine or drive

In CPG we can see HA set as mag which means it's drive level redundandancy in order to create RAID set. 

You can go through 3PAR Concepts Guide and Architecture document that may help,

https://support.hpe.com/hpesc/public/docDisplay?docId=c04204225

https://h20195.www2.hpe.com/v2/getpdf.aspx/4aa3-3516enw.pdf

 

Hope this helps!
Regards
Subhajit

I am an HPE employee

If you feel this was helpful please click the KUDOS! thumb below!

************************************************************************


I work for HPE
Accept or Kudo