] > ] > 1. I don't think I've ever seen a Linux distro which has write
] > ] > caching enabled by default. Hell, DMA33 isn't even enabled
] > ] > by default ;)
] > ]
] > ] You are talking about controlling the IDE drive cache.
] > ]
] > ] The issue here is write cache in the filesystem code.
] >
] > No. The issue here is the write cache on the drive.
] > FreeBSD with soft updates will operate within 4% of the top memory
] > bandwidth; see the Ganger/Patt paper on the technology.
]
] I have a file, CSE-TR-254-95.ps, that I think is probably the paper
] you are talking about. The title is "Soft Updates: A Solution to the
] Metadata Update Problem in File Systems". The link on Ganger's page was
] dead, but I'm sure this is the one you mean.
]
] Nowhere do they support the idea that soft udpates can approach a
] system's memory bandwidth.
I said "top memory bandwidth", not "a system's memory bandwidth";
please be more careful.
Quoting from section 6, "Conclusions and Future Work":
We have described a new mechanism, soft updates, that
can be used to achieve memory-based file system
************************
performance while providing stronger integrity and
***********
security guarantees (e.g. allocation initialization)
and higher availability (via shorter recovery times)
than most UNIX file systems. This translates into a
performance improvement of more than a factor fo 2
in many cases (up to a maximum observed difference
of a factor of 15).
Terry Lambert
[EMAIL PROTECTED]
---
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