Machine limits

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ICP IOCP supports the following limits:
Table 1. Constant machine limits
Machine limits
Control unit headers (CUHs)
Maximum channel paths per CUH 8
Physical control units (PCUs)
Maximum PCUs per CVC or CBY channel path (Note 1) 48
Maximum PCUs per CFS, CFP, CBS, CBP, ICP, CIB, CL5, CS5, FCP, OSC, OSE, or OSN channel path 1
Maximum PCUs or link addresses per CNC or CTC channel path 120
Maximum PCUs or link addresses per FCV or FC channel path (Note 5) 256
Maximum PCUs per IQD channel path 64
Maximum PCUs per OSD, OSM, or OSX channel path 16
Maximum UA ranges per CVC or CBY channel path 64
Maximum UA ranges per shared CTC channel path 120
Maximum UA ranges per FC channel path (Note 6) 256
Maximum UAs per CNC channel path 1024
Maximum UAs per CTC channel path 512
Maximum UAs per FCV channel path 16 K*
Maximum channel paths per PCU (Note 3) 8
Devices
Maximum devices per CVC, CBY, CFS, CFP, CBS, CBP, CIB, CL5, CS5, or ICP channel path 256
Maximum devices per CNC channel path 1024
Maximum devices per CTC channel path 512
Maximum devices per OSC channel path (Note 6) 254
Maximum devices per OSE channel path (Note 6) 255
Maximum devices or subchannels per OSD or OSX channel path with priority specification enabled 480
Maximum devices or subchannels per OSD, OSM, or OSX channel path with priority specification disabled (CHPARM=02; Note 7) 1920
Maximum UNIT=OSN devices or subchannels per OSN channel path 480
Maximum UNIT=3745 devices or subchannels per OSN channel path 180
Maximum devices or subchannels per FCP channel path (Note 9) 480
Maximum devices or subchannels per FCV channel path 16 K
Maximum devices or subchannels for all IQD channel paths 12 K
Maximum channel paths per device (Note 4) 8
Maximum PCUs per device (Note 4) 8
Channel paths
Valid chpid range per CSS (Note 2) 00-FF
Maximum channel paths per CIB AID 16
Maximum channel paths per CS5 AID port 4
Maximum channel paths per CL5 PCHID port 4
Maximum port value for CL5 or CS5 2
IOCDS Levels A0-A3
Functions
Maximum port value for HYL or ROC2 2
Logical partitions
Maximum logical partitions per CSS (Note 8) 15
*K=1024
Notes:
  1. The IOCP maximum of 48 allows you to over-define control units (possibly on a switch) for a path. However, do not use more than eight control units on a path at one time.
  2. All chpid range values are hexadecimal. You can specify the maximum chpid range even though your CPC might have only a subset of the channel paths installed.
  3. If you define the PCU as an ESCON CTC (UNIT=SCTC) or FICON® CTC (UNIT=FCTC) control unit or attach the PCU to an FCP, IQD, OSC, OSD, OSE, OSM, OSN, or OSX channel path, the PCU can attach to only one channel path per CSS.
  4. If the device attaches to a PCU that you defined as an ESCON CTC or FICON CTC control unit or the PCU attaches to an FCP, IQD, OSC, OSD, OSE, OSM, OSN, or OSX channel path, the device can attach to only one PCU and to one channel path per CSS.

    If the device attaches to a PCU attached to CFS, CFP, CBS, CBP, ICP, CIB, CL5, CS5 channel paths, the device can attach to only one PCU.

  5. FCV channel paths can have link addresses in the range 01-FE and, therefore, have a maximum of 254 link addresses.
  6. You can use a maximum of 240 OSA valid subchannels on an OSE channel path even though IOCP permits you to define more than this number. You can use a maximum of 120 valid subchannels on an OSC channel path, even though IOCP permits you to define more than this number. See OSA configuration considerations for more information.
  7. OSA-Express2 and later features are required when disabling priority specification on OSD channel paths (for example, specifying CHPARM=02 on the CHPID statement). OSM channel paths always operate with priority queuing disabled. OSM and OSX channel paths require OSA-Express3 or later features.
  8. On 3932, 3931, 8562, 8561, 3907, 3906, 2965 and 2964 models, the maximum CSS ID supported by the CPC can only contain 10 logical partitions with MIF IDs in the range 1-A. The LMC partition MCS_1 (also known as a firmware partition) does not count against the maximum of 10 logical partitions and MCS_1 must have MIF ID B. To determine if your CPC supports the MCS_1 partition, see Table 1.
  9. If an FCP channel path is dedicated to a logical partition, the maximum number of devices is 254.

ICP IOCP supports the following limits for the following CPCs (machine types):

Table 2. Machine limits
Machine Limit Machine type (Note 1)
2817,1 2818,1 2827,1 2828,1 2964,1 2965,1 3906,1 3907,1 8561,1 8562,1 3931,1 3932,1
Devices or subchannels
Maximum devices or subchannels per CSS for subchannel set 0 65280 (63.75 K*) 65280 (63.75 K*) 65280 (63.75 K*) 65280 (63.75 K*) 65280 (63.75 K*) 65280 (63.75 K*) 65280 (63.75 K*) 65280 (63.75 K*) 65280 (63.75 K*) 65280 (63.75 K*) 65280 (63.75 K*) 65280 (63.75 K*)
Maximum devices or subchannels per CSS for subchannel set other than 0 65535 (64 K*-1) 65535 (64 K*-1) 65535 (64 K*-1) 65535 (64 K*-1) 65535 (64 K*-1) 65535 (64 K*-1) 65535 (64 K*-1) 65535 (64 K*-1) 65535 (64 K*-1) 65535 (64 K*-1) 65535 (64 K*-1) 65535 (64 K*-1)
Maximum devices (UAs) per FC channel path (Note 6) 16K 16K 24K 24K 32K 32K 32K 32K 32K 32K 32K 32K
Channel subsystems (CSSs) and subchannel sets
Maximum CSS ID 3 1 3 1 5 2 5 2 5 2 5 2
Maximum subchannel set ID 2 1 2 1 3 2 3 2 3 2 3 2
Logical partitions
Maximum logical partitions (Note 2) 60 30 60 30 85 40 85 40 85 40 85 40
Maximum I/O Clusters 64 64 64 64 128 128 128 128 128 128 128 128
Control unit headers (CUHs)
Maximum CUHs per CSS 4096 4096 4096 4096 4096 4096 4096 4096 4096 4096 4096 4096
Physical control units (PCUs)
Maximum PCUs 8192 8192 8192 8192 8192 8192 8192 8192 8192 8192 8192 8192
Channel paths or functions
Maximum PCHID number 6FF 2FF 6FF 2FF 37F 2FF 37F 1FF 3FF 1FF 3FF 1BF
Minimum VCHID Number N/A N/A N/A N/A 7C0 7C0 7C0 7C0 7C0 7C0 7C0 7C0
Maximum VCHID Number N/A N/A N/A N/A 7FF 7FF 7FF 7FF 7FF 7FF 7FF 7FF
Minimum AID number for CIB 0 0 0 0 0 0 0 N/A N/A N/A N/A N/A
Maximum AID number for CIB 1F 0B 1F 0B 0F 0F 0F N/A N/A N/A N/A N/A
Maximum CIB AIDs 16 8 16 8 16 8 16 N/A N/A N/A N/A N/A
Maximum CIB port value 4 4 4 4 4 4 4 N/A N/A N/A N/A N/A
Minimum AID number for CS5 N/A N/A N/A N/A 10 10 10 10 00 00 00 00
Maximum AID number for CS5 N/A N/A N/A N/A 37 37 37 37 3B 17 2F 17
Maximum CS5 AIDs N/A N/A 16 16 20 8 40 8 48 24 48 24
Maximum CL5 PCHIDs N/A N/A N/A N/A 32 16 32 16 32 32 32 32
Maximum channel paths 704 (Note 4) 464 528 320 608 448 608 352 800 480 792 472
Maximum CVC, CBY, CNC, or CTC channel paths 240 (Note 4) 240 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A
Maximum FCV, FC, FCP, OSC, OSD, OSE, OSM, OSN, or OSX channel paths (Note 3) 352 160 368 160 320 160 320 128 384 128 384 96
Maximum FCP channel paths 256 160 256 160 256 160 256 128 384 128 384 96
Maximum OSC, OSD, OSE, OSM, OSN, or OSX channel paths 48 48 48 48 48 48 48 48 48 48 48 48
Maximum CFS, CFR, CFP, CBS, CBR, CBP, CIB, CL5, CS5 or ICP channel paths 128 128 128 128 256 256 256 224 384 384 384 384
Maximum CIB, CL5, CS5, or ICP channel paths per logical partition 128 128 128 128 128 128 128 128 128 128 128 128
Maximum CFS, CFR, or CFP channel paths 48 48 48 48 N/A N/A N/A N/A N/A N/A N/A N/A
Maximum ICP channel paths 32 32 32 32 32 32 32 32 64 64 64 64
Maximum IQD channel paths 32 32 32 32 32 32 32 32 32 32 32 32
Maximum function adapters (PCHIDs) N/A N/A 24 16 40 40 72 60 48 40 48 40
Maximum function ID (FID) N/A N/A FF FF 22FF 22FF 47FF 47FF 47FF 47FF 47FF 47FF
Maximum HYL PCHIDs N/A N/A N/A N/A N/A N/A 16 16 16 16 16 16
Maximum ISM VCHIDs N/A N/A N/A N/A 32 32 32 32 32 32 32 32
Maximum NVME PCHIDs N/A N/A N/A N/A N/A N/A 16 16 16 16 16 16
Maximum RCE PCHIDs N/A N/A N/A N/A 16 16 16 16 N/A N/A N/A N/A
Maximum ROCE PCHIDs N/A N/A 16 16 16 16 8 4 16 8 N/A N/A
Maximum ROC2 PCHIDs N/A N/A N/A N/A N/A N/A 8 4 16 8 16 8
Maximum ROCE or ROC2 PCHIDs N/A N/A N/A N/A N/A N/A 8 4 16 8 16 8
Maximum ROCE and ROC2 PCHIDs per resource group N/A N/A N/A N/A N/A N/A 2 1 4 2 4 2
Maximum ZEDC PCHIDs N/A N/A 8 8 8 8 16 8 N/A N/A N/A N/A
Maximum VFs per ROC2 port N/A N/A N/A N/A N/A N/A 63 31 63 31 63 31
IOCP storage requirement
Minimum storage required by IOCP 108 MB* 40 MB* 108 MB* 40 MB* 214 MB* 86 MB* 213 MB* 85 MB* 213 MB* 85 MB* 215 MB* 86 MB*
*K=1024. MB=1 048 576 bytes.
Table 3. Valid CHPID types
CHPID type Machine type (See Note 1)
2817,1 2818,1 2827,1 2828,1 2964,1 2965,1 3906,1 3907,1 8561,1 8562,1 3931,1 3932,1
CBY Yes Yes No No No No No No No No No No
CVC Yes Yes No No No No No No No No No No
CNC Yes Yes No No No No No No No No No No
CTC Yes Yes No No No No No No No No No No
CFS No No No No No No No No No No No No
CFR No No No No No No No No No No No No
CFP Yes Yes Yes Yes No No No No No No No No
CBS No No No No No No No No No No No No
CBR No No No No No No No No No No No No
CBP No No No No No No No No No No No No
CIB (Note 5) Yes Yes Yes Yes Yes Yes Yes No No No No No
CL5 (Note 8) No No No No Yes Yes Yes Yes Yes Yes Yes Yes
CS5 No No No No Yes Yes Yes Yes Yes Yes Yes Yes
FC Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
FCV No No No No No No No No No No No No
FCP Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
ICP Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
IQD Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
OSC Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
OSD Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
OSE Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
OSM Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes No No
OSN Yes Yes Yes Yes Yes Yes No No No No No No
OSX Yes Yes Yes Yes Yes Yes Yes Yes No No No No

Machine types not listed do not support function adapters.

Table 4. Valid FUNCTION types
FUNCTION type Machine type (See Note 1)
2827,1 2828,1 2964,1 2965,1 3906,1 3907,1 8561,1 8562,1 3931,1 3932,1
HYL No No No No Yes Yes Yes Yes Yes Yes
ISM (See Note 9) No No Yes Yes Yes Yes Yes Yes Yes Yes
NVME (See Note 10) No No No No Yes Yes Yes Yes Yes Yes
RCE (See Note 9) No No Yes Yes Yes Yes No No No No
ROCE (See Note 7 ) Yes Yes Yes Yes Yes Yes Yes Yes No No
ROC2 No No No No Yes Yes Yes Yes Yes Yes
ZEDC (See Note7 ) Yes Yes Yes Yes Yes Yes No No No No
Notes:
  1. Machine type refers to the value specified in the SYSTEM keyword of the ID statement.
    • SYSTEM=(2817,1) specifies a 2817 Model M15, M32, M49, M66, or M80.
    • SYSTEM=(2818,1) specifies a 2818 zEnterprise® 114 Model M05 or M10.
    • SYSTEM=(2827,1) specifies a 2827 zEnterprise EC12 Models H20, H43, H66, H89, or HA1.
    • SYSTEM=(2828,1) specifies a 2828 zEnterprise BC12 Models H06 or H13.
    • SYSTEM=(2964,1) specifies a 2964 Model N30, N63, N96, NC9, NE1, L30, L63, L96, LC9, or LE1.
    • SYSTEM=(2965,1) specifies a 2965 Model N10, N20, L10, or L20.
    • SYSTEM=(3906,1) specifies a 3906 Model M01, M02, M03, M04, M05, LM1, LM2, LM3, LM4, or LM5.
    • SYSTEM=(3907,1) specifies a 3907 Model ZR1 or LR1.
    • SYSTEM=(8561,1) specifies a 8561 Model T01 or LT1.
    • SYSTEM=(8562,1) specifies a 8562 Model T02 or LT2.
    • SYSTEM=(3931,1) specifies a 3931 Model A01 or LA1.
    • SYSTEM=(3932,1) specifies a 3932 Model A02, LA2, AGZ, or AGL.
  2. The LMC partition MCS_1 (also known as a firmware partition) does not count against the maximum number of partitions you can define. To determine if your CPC supports the MCS_1 partition, see Table 1.
  3. You are informed if you define more than the maximum number of channel paths. This maximum number of channel paths is determined by the maximum number of cards that can be installed in the processor and can be reached only if every card is a FICON card. Also, this maximum includes PCI Cryptographic and Flash Express cards installed on your CPC. However, PCI Cryptographic and Flash Express cards are not defined to IOCP, and IOCP cannot include them in its checking of this maximum. Also, function adapter cards (for example, zEDC Express) use FUNCTION statements for their definition instead of CHPID statements and are excluded from the maximum channel path check. The following table summarizes the maximum for each type of CPC:
    Table 5. Maximums by CPC
    CPC Maximum number of cards
    3932 48
    3931 192
    8562 64
    8561 192
    3907 64
    3906 160
    2965 80
    2964 160
    2828 80
    2827 168
    2818 72
    2817 168
  4. RPQs might be available to increase these values.
  5. CIB channel paths are supported as follows:
    • On all ECs of any other CPC that supports the CIB channel path type.
  6. IOCP might generate more unit address ranges and unit addresses for a spanned FC channel path than for an unspanned channel path. See FC control unit definition considerations:. The 2827 models support 16K devices (UAs) at EC H09173 and 24K devices (UAs) at EC H49564.
  7. The 2827 and 2828 models support RoCE and zEDC function adapters but ignore the FUNCTION TYPE keyword.
  8. CL5 channel paths are supported as follows:
    • On 2965 and 2964 models at EC P00339 (with an LMC patch installed)
    • On all ECs of any other CPC that supports the CL5 channel path type.
  9. The 2964 models support ISM and RCE functions at EC P00339.
  10. The 3907 and 3906 models support NVME functions at EC P41414.
  11. A maximum of 128 NPIV-enabled subchannels are supported on 3932 and 3931 models (with an LMC patch installed) for FICON Express32S. Otherwise, a maximum of 64 NPIV-enabled subchannels are supported.
Table 6. FCP Channel Path Limits
Limit or Recommendation FICON Express 8/8S FICON Express 16S/16S+/16SA/32SA/32S
Maximum configurable devices or subchannels per FCP channel path 480 480
Recommended maximum number of active NPIV-enabled subchannels per FCP channel path 32 64 or 128 ( Note 11)
Maximum number of remote N_Ports per FCP channel path 512 1024
Maximum concurrent I/O operations per FCP channel path 960 1528
Maximum number of LUNs that can be open at the same time 4096 8192