Highlighted

Number of Plexes

Hello,

can anyone tell me the maximum number of plexes that can be attached to a volume. Is there any page for such kind of metrics, like, max vol size, max FS size, etc. Can anyone who knows these "Numbers" could create a page?

1 Solution

Accepted Solutions
Accepted Solution!

This information is

This information is documented in the VxVM Administrator's Guide and the VxFS Administrator's Guide - see below.

Note: As this information is already readily available in the existing documentation, there doesn't seem much point "creating a page", since this is unnecessary duplication / may become obsolete/incorrect as versions are updated/changed.

Maximum number of plexes:
per VxVM 5.1 (Solaris) Administrator's Guide p554 (https://sort.symantec.com/public/documents/sf/5.1/solaris/pdf/vxvm_admin.pdf or direct html version here: https://sort.symantec.com/public/documents/sf/5.1/solaris/html/vxvm_admin/ch16s02s01.htm )
RAID5 - Volume Read Policies
"To improve performance for read-intensive workloads, you can attach up to 32 data plexes to the same volume. However, this approach is usually an ineffective use of disk space for the gain in read performance."

Maximum volume size
VxVM Administrator's Guide -> Ch8 Creating Volumes -> Discovering the maximum size of a volume (p317-318)
https://sort.symantec.com/public/documents/sf/5.1/solaris/html/vxvm_admin/ch08s05.htm
[...skip to last paragraph...]
The maximum size of a VxVM volume that you can create is 256TB.

Maxiumum filesystem size
This depends on the Disk layout version of the filesystem
VxFS 5.1 (Solaris) Administrator's Guide -> Appendix C Disk Layout (p229)
https://sort.symantec.com/public/documents/sf/5.1/solaris/pdf/vxfs_admin.pdf
https://sort.symantec.com/public/documents/sf/5.1/solaris/html/vxfs_admin/apcs01.htm

(p230) Version 4 supports files and file systems up to one terabyte in size.
(p230) Version 5 enables the creation of file system sizes up to 32 terabytes. File sizes can be a maximum of 4 billion file system blocks. File systems larger than 1TB must be created on a Veritas Volume Manager volume.
(p234) The Version 6 disk layout can theoretically support files and file systems up to 8 exabytes (2^63). The maximum file system size that can be created is currently restricted to 2^35 blocks. For a file system to take advantage of greater than 1 terabyte support, it must be created on a Veritas Volume Manager volume. For 64-bit kernels, the maximum size of the file system you can create depends on the block size [table omitted]
(p235) The Version 7 disk layout can theoretically support files and file systems up to 8 exabytes (2^63). The maximum file system size that can be created is currently restricted to 2^35 blocks.[...]

Hope that helps,

Grace

View solution in original post

2 Replies
Accepted Solution!

This information is

This information is documented in the VxVM Administrator's Guide and the VxFS Administrator's Guide - see below.

Note: As this information is already readily available in the existing documentation, there doesn't seem much point "creating a page", since this is unnecessary duplication / may become obsolete/incorrect as versions are updated/changed.

Maximum number of plexes:
per VxVM 5.1 (Solaris) Administrator's Guide p554 (https://sort.symantec.com/public/documents/sf/5.1/solaris/pdf/vxvm_admin.pdf or direct html version here: https://sort.symantec.com/public/documents/sf/5.1/solaris/html/vxvm_admin/ch16s02s01.htm )
RAID5 - Volume Read Policies
"To improve performance for read-intensive workloads, you can attach up to 32 data plexes to the same volume. However, this approach is usually an ineffective use of disk space for the gain in read performance."

Maximum volume size
VxVM Administrator's Guide -> Ch8 Creating Volumes -> Discovering the maximum size of a volume (p317-318)
https://sort.symantec.com/public/documents/sf/5.1/solaris/html/vxvm_admin/ch08s05.htm
[...skip to last paragraph...]
The maximum size of a VxVM volume that you can create is 256TB.

Maxiumum filesystem size
This depends on the Disk layout version of the filesystem
VxFS 5.1 (Solaris) Administrator's Guide -> Appendix C Disk Layout (p229)
https://sort.symantec.com/public/documents/sf/5.1/solaris/pdf/vxfs_admin.pdf
https://sort.symantec.com/public/documents/sf/5.1/solaris/html/vxfs_admin/apcs01.htm

(p230) Version 4 supports files and file systems up to one terabyte in size.
(p230) Version 5 enables the creation of file system sizes up to 32 terabytes. File sizes can be a maximum of 4 billion file system blocks. File systems larger than 1TB must be created on a Veritas Volume Manager volume.
(p234) The Version 6 disk layout can theoretically support files and file systems up to 8 exabytes (2^63). The maximum file system size that can be created is currently restricted to 2^35 blocks. For a file system to take advantage of greater than 1 terabyte support, it must be created on a Veritas Volume Manager volume. For 64-bit kernels, the maximum size of the file system you can create depends on the block size [table omitted]
(p235) The Version 7 disk layout can theoretically support files and file systems up to 8 exabytes (2^63). The maximum file system size that can be created is currently restricted to 2^35 blocks.[...]

Hope that helps,

Grace

View solution in original post

Thanks Grace!

Thanks a lot Grace for your reply. I meant it could be one single page/doc where we could access these Info which now is spread among different docs.