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Separate Write/Read Logical Paths to Optimize Library Network File System Data Rates

IP.com Disclosure Number: IPCOM000113691D
Original Publication Date: 1994-Sep-01
Included in the Prior Art Database: 2005-Mar-27
Document File: 2 page(s) / 64K

Publishing Venue

IBM

Related People

Butka, DJ: AUTHOR [+4]

Abstract

To improve both the write and read Effective Data Rates (EDRs) for optical libraries attached via Transmission Control Protocol/Internet Protocol (TCP/IP) and Network File System (NFS), we propose two logical paths to the same physical library. A W: drive denotes the write path and a R: drive denotes the read path.

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Separate Write/Read Logical Paths to Optimize Library Network File
System Data Rates

      To improve both the write and read Effective Data Rates (EDRs)
for optical libraries attached via Transmission Control
Protocol/Internet Protocol (TCP/IP) and Network File System (NFS), we
propose two logical paths to the same physical library.  A W: drive
denotes the write path and a R: drive denotes the read path.

      To improve NFS EDRs, we propose the redirecting of write
workloads through the LAN Server microcode, as shown in Fig. 1.
Although this path is longer from a microcode standpoint, the LAN
server acknowledges but does not obey the repetitive open/close
commands of TCP/IP for every incremental buffer.  This causes the
redirected write EDR to improve over sending the write workload
directly to the Installable File System (IFS), as shown in the Table.

      Read workloads would not be redirected.  The longer microcode
path through the LAN server impedes the read EDR, as shown in the
Table.  Thus, the better read EDR is achieved via bypassing the LAN
server microcode and sending the read workload only through IFS to
TCP/IP.

Table.   NFS Effective Data Rate (1 Drive) in KB/s versus File Size
  Workload   Redirected                     File Size
             to Lan Server     4 KB     50 KB     300 KB     1000 KB
  Write      No                 1        2         3          3
  Write      Yes                1        3        18         30
  Read       No                10       37        40         37
  Read       Yes                8       28        32...