An important aspect of linear controller design is to clarify whether the d
esign reaches the performance limit, which is highly significant to the pra
ctice of control system design. Based on an industrial project of a high-pr
ecision gyro test table (servo system), a paradigm is presented to demonstr
ate that the performance limit of the disturbance attenuation design of the
servo system can be reached in a systematic way by using CI synthesis. A g
yro test table is a servo system employed to measure the drift of a gyro. I
n contrast with general sensitivity theory, which generally considers the o
utput disturbance rejection, the main concern in gyro test table design is
the input disturbance attenuation. The uncertainty caused by the neglected
dynamics in this servo design implies a limitation on the bandwidth of the
gyro test table, i.e. the bandwidth is limited by the robust stability requ
irement. Furthermore, it is manifested that the multiplicative uncertainty
description plays a leading role in the H-infinity/mu design. This paper re
veals that the performance limit is determined by the bandwidth. This findi
ng will help the designer to judge whether any given performance specificat
ion is achievable and illustrates the design idea of giving priority to the
bandwidth.