zPulse · Disk · Formerly EADM
zPulse Disk splits every I/O into IOSQ, pending, disconnect and connect time, by LPAR, LCU, volume and period, from your RMF or CMF reports. It is the analysis EADM made, rebuilt with history and scheduling.
A DASD response time analysis on z/OS starts with one question: is the delay in z/OS queuing, on the channel path, or in the storage system? zPulse Disk answers it from the reports you already produce, for one LPAR or for a whole sysplex, and shows when and on which volumes it happens.
zPulse Disk is the module for I/O and storage-system performance. It reads the DASD, cache, channel and queuing pages of your RMF or CMF reports and turns them into one study you can browse by LPAR, period, LCU, volume and storage group.
What it analyses
IOSQ, pending, disconnect and connect time, with the I/O rate, per LPAR and per period. Filters for TP, batch or both.
The 3390 devices and volumes with the highest response time or I/O rate, and the space used on each volume.
Track and read cache misses, delayed I/O, and workload against memory and disk, to compare before and after a cache or microcode change.
Front-end and back-end throughput and block size, and back-end activity of the storage system.
Channel use by LCU, I/O topology flow, HyperPAV activity, and zHyperLink I/O (RMF reports only).
From a CMF dataset activity listing: I/O by dataset, job or volume, over 24 hours or the sum of 15-minute intervals.
In the application
These are the report tabs of a study in the zPulse application.
The report tabs of a disk study in the zPulse application.
Data
zPulse works from the reports and files you already produce. Nothing is installed on z/OS.
| Record or file | Report | What zPulse uses it for |
|---|---|---|
| SMF 74.1 | Direct Access Device Activity (RMF), Device Activity (CMF) | Response time components, I/O rate, activity per device, volume and storage group. |
| SMF 74.5 | Cache Subsystem Activity | Cache hits and misses, delayed I/O, front-end and back-end activity. |
| SMF 78.3 | I/O Queuing Activity | I/O processor utilisation and I/O interrupt rate. |
| SMF 73 | Channel Path Activity | FICON channel utilisation and read and write throughput. |
| SMF 42 | CMF Dataset Activity (42.6) | I/O by dataset, job and volume. |
| RMF | Synchronous I/O Device Activity (RMF) | The zHyperLink screen. RMF reports only: the screen stays empty for CMF files. |
| SMF 70.1 | Power Consumption (RMF) | Electricity consumption of the I/O. Needs z/OS 3.1 or later with POWERMETRICS; CMF files carry no power data. |
SMF 74.1
SMF 74.5
SMF 78.3
SMF 73
SMF 42
RMF
SMF 70.1
Tools
Tools open a report or a folder and show charts and tables on one subject. Each card of the catalogue says which file the tool reads.
Automatic studies
A scheduled disk study sends a DASD report by mail: per-period charts of the response time components, worst-volume tables, and the previous days as charts of up to 60 days. The period covered is in the subject.
EADM profiled your I/O from RMF and CMF reports, by LPAR or for a whole sysplex, and mailed the results. zPulse Disk keeps that analysis and adds the studies, history and cache, FICON and topology views listed above.
I/O response time by hour (ms), stacked by component
Previous days: average response time (ms)
The mail charts up to 60 previous days.
| Volume | Resp (ms) | IOSQ (ms) |
|---|---|---|
| DB2L03 | 0.61 | 0.12 |
| DB2L07 | 0.52 | 0.09 |
| PRD104 | 0.47 | 0.04 |
Period: 7 Oct 2026 · Charts are in the body of the mail, with no attachment.
FAQ
RMF post-processor reports and CMF reports, as text files, for one LPAR or for all the LPARs of a sysplex. The reports are produced from SMF records 74.1, 74.5, 78.3 and 73, and CMF dataset activity from SMF 42.
Into IOSQ (queued in z/OS before the I/O starts), pending (waiting for a channel path, control unit or device), disconnect (for example waiting on cache or on the back end) and connect (data transfer). zPulse charts the four components and the total.
Most are. The zHyperLink screen and the two electricity screens read RMF reports only, and stay empty for CMF files.
No. zPulse reads the report files you already produce. It runs on its own server.
Yes. A scheduled study runs at a daily time on the files in a folder and sends the result by mail, with the covered period in the subject.
No. It is optional and runs on Ollama on the same machine as zPulse. Without it, studies run as usual.
zPulse
Formerly EATM
Tape catalogue capacity, virtual tape mounts and response time, TS7700 VEHSTATS statistics.
Formerly EAMC
MSU used, R4HA, LPAR activity, WLM workloads and service classes.
DCOLLECT studies
Allocated and free space, fragmentation and defrag score by LPAR, storage group and volume.
Send us an extract. A Technical Storage expert runs it through zPulse and walks you through the results.