Zhang, M. Deng, R.B. Gu, D. Gu, Q. Huang, D. Wang, Z. JACoW Geneva, Switzerland 978-3-95450-182-3 10.18429/JACoW-IPAC2017-TUPAB084 English 1513-1516 TUPAB084 linac FEL controls quadrupole klystron Contribution to a conference proceedings 2017 2017-05 http://dx.doi.org/10.18429/JACoW-IPAC2017-TUPAB084 http://jacow.org/ipac2017/papers/tupab084.pdf FEL operations foresee stringent requirements for the stability of the global linac output parameters and this requirement is particularly stringent for the successful operation of an externally seeded FEL. In order to understand the sensitivity of these parameters to jitters of various error sources along the SXFEL linac, studies have been performed based on analytical methods and tracking code simulations. Using the tolerance budget as guidance, beam jitter control techniques are discussed on the view of the beam dynamics.