| Abstract | Timestamp–based algorithms have been proposed to protect distributed
database from inconsistencies during concurrent access. In such algorithms,
transactions may reach a paricular site out of the order of their timestamps,
due to unexpected network delays. This causes conflicts which the distributed
concurrency control mechanism has to cope with. In this paper we analyze
the essential features of the conflict phenomenon under the realistic assumption
of the local site clocks out of total synchrony. We quantify the way in
which local clock inaccuracies affect the phenomenon of transaction conflicts.
In particular, we express the probability of order–reverse as a particular increasing
function of the maximum clock drift.
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