<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class="">Hello there,</div><div class=""><br class=""></div><div class="">I have been confused of the extent of the available preconditioners in PETSc for a while. Here are the lists I got from one slide of a lecture notes saying</div><div class=""><br class=""></div><div class="">Block Jacobi,</div><div class="">Jacobi,</div><div class="">Overlapping Additive Schwarz,</div><div class="">ICC, ILU (sequential only)</div><div class="">ILU(K), LU(direct solver, sequential only)</div><div class="">sor</div><div class="">etc.</div><div class=""><br class=""></div><div class=""><br class=""></div><div class="">But in some other sources, only LU is highlighted with "sequential only". Which one is correct? I am using MATCreateAIJ to construct my A. Which preconditioner is available to me? By the way, I tested asm, ilu, icc, and they all failed. </div><div class=""><br class=""></div><div class="">Thanks,</div><div class="">Paul</div><div apple-content-edited="true" class=""><div style="color: rgb(0, 0, 0); letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div style="color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class=""><font size="1" class=""><br class=""></font></div></div></div></div></div></body></html>