We report the results of a multiyear spectroscopic and photometric monitoring campaign of two luminous quasars, PG0923+201 and PG1001+291, both located at the high-luminosity end of the broad-line region (BLR) size-luminosity relation with optical luminosities above 1045erg/s. PG0923+201 is monitored for the first time, while PG1001+291 was previously monitored but our campaign has a much longer temporal baseline. We detect time lags of variations of the broad H{beta}, H{gamma}, and FeII lines with respect to those of the 5100{AA} continuum. The velocity-resolved delay map of H{beta} in PG0923+201 indicates a complicated structure with a mix of Keplerian disk-like motion and outflow, and the map of H{beta} in PG1001+291 shows a signature of Keplerian disk-like motion. Assuming a virial factor of fBLR=1 and FWHM line widths, we measure the black hole mass to be 118_-16_^+11^x10^7^M{sun} for PG0923+201 and 3.33_-0.54_^+0.62^x10^7^M{sun} for PG1001+291. Their respective accretion rates are estimated to be 0.21_-0.07_^+0.06^xL_Edd_c^-2^ and 679_-227_^+259^xL_Edd_c^-2^, indicating that PG0923+201 is a sub-Eddington accretor and PG1001+291 is a super-Eddington accretor. While the H{beta} time lag of PG0923+201 agrees with the size-luminosity relation, the time lag of PG1001+291 shows a significant deviation, confirming that in high-luminosity active galactic nuclei (AGNs), the BLR size depends on both luminosity and Eddington ratio. Black hole mass estimates from single-AGN spectra will be overestimated at high luminosities and redshifts if this effect is not taken into account.