IBM TS7700 Overview - page 6
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Page 6
Table 1. Virtual Tape Subsystem Comparison
Feature
IBM TS7740
Sun VSM 5
IBM
Score
1
Sun
Score
1
Maximum Number of Virtual Tape
Drives per Single Node/Multi-Node
256/768
256 1
Maximum Number of Nodes
3 (arch. for 8)
2
Maximum Peak Throughput per Node
2
800 MB/s
650 MB/s
1
Maximum Sustained Write Throughput
per Node
3
550 MB/s
613 MB/s
1
Data Compression Ratio – System z
4:1
4:1
Maximum Disk Cache Raw Capacity
6 TB
7 TB
1
Maximum Effective Disk Cache
Capacity (4:1 Compression)
24 TB
28 TB
1
General Availability
2H06
2H06
System z Attachment
1, 2, and 4 Gbps
FICON
(auto negotiate)
2 Gbps FICON
1
FICON Concurrent I/O Support per port
32
16 1
Open Systems Attachment
None
None
Maximum Number of FICON Channels
per node
4 (4Gbps)
16
See
text on
Perfor-
mance
See
text on
Perfor-
mance
Maximum Number of FC links to real
tape drives per node
2 - 4Gbps paths
to all real tape
drives
None –
channels must
be dedicated
to host, tape
drive and
cluster links
1
Gigabit TCP/IP links
2
0 1
Maximum Number of Real Tape Drives
per node
16
32
1
Maximum Number of Virtual Tape
Volumes
1,000,000
Not limited
1
Synchronous Replication
Yes
None publicly
announced
1
Asynchronous Replication
Yes
Yes
On-demand Disk Cache upgrades
Yes
No 1
On-demand Performance upgrades
Yes
No 1
Maximum Power
Consumption/dissipation
3.2 KVA; 11.0
KBTU/hour
3.8 KVA;12.4
KBTU/hour
1
Score Totals
10
5
Notes:
1 - This score is a simple binary -- which vendor has better specifications
2 - Depends on lots of things including compression ratio, read/write ratio, block size, etc.
3 - Depends on features and updates installed
Sources: IBM, Sun, and Google