Bruce Momjian wrote:
> Agreed, thought I thought the problem was that SSDs lie about their
> cache flush like SATA drives do, or is there something I am missing?
There's exactly one case I can find where this century's IDE
drives lied more than any other drive with a cache:
Under 120GB Maxtor drives from late 2003 to early 2004.
and it's apparently been worked around for years.
Those drives claimed to support the "FLUSH_CACHE_EXT" feature (IDE
command 0xEA), but did not support sending 48-bit commands which
was needed to send the cache flushing command.
And for that case a workaround for Linux was quickly identified by
checking for *both* the support for 48-bit commands and support for the
flush cache extension.
Beyond those 2004 drive + 2003 kernel systems, I think most the rest
of such reports have been various misfeatures in some of Linux's
filesystems (like EXT3 that only wants to send drives cache-flushing
commands when inode change) and linux software raid misfeatures....
...and ISTM those would affect SSDs the same way they'd affect SATA drives.
In response to
pgsql-performance by date
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