<div dir="ltr"><div>Dear QE Users,</div><div><p style="line-height:100%;margin-bottom:0.1in;background:transparent"><span style="font-family:arial,sans-serif">I am encountering a memory allocation
error while running the SCF calculation for Ag2O. The error message
reads:</span></p>
<p style="line-height:100%;margin-bottom:0.1in;background:transparent"><span style="font-family:arial,sans-serif"><br></span>
<span style="font-family:arial,sans-serif"><br></span>
</p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">Operating system
error: Cannot allocate memory</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">Allocation would
exceed memory limit</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><span style="font-family:arial,sans-serif"><br></span>
</p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">Error
termination. Backtrace:</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">#0
0x7f2002230d11 in ???</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">#1
0x7f2002231859 in ???</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">#2
0x7f2002231ab4 in ???</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">#3
0x55c4ee92b405 in ???</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">#4
0x55c4ee8c8d24 in ???</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">#5
0x55c4ee98a967 in ???</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">#6
0x55c4ee8bf3b3 in ???</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">#7
0x55c4ee8bf0ce in ???</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">#8
0x7f2001eb3082 in __libc_start_main</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif"> at
../csu/libc-start.c:308</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">#9
0x55c4ee8bf0fd in ???</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">#10
0xffffffffffffffff in ???</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><span style="font-family:arial,sans-serif"><br></span>
</p>
<p style="font-weight:normal;line-height:100%;margin-bottom:0.1in;background:transparent"><span style="font-family:arial,sans-serif">Despite upgrading
my RAM from 7.6 GB to 11.6 GB, I am still experiencing this issue.
Could the choice of exchange-correlation functional (</span>HSE)<span style="font-family:arial,sans-serif"> be contributing
to this problem? If so, could you suggest any adjustments or
alternatives to complete my calculation?</span></p>
<p style="font-weight:normal;line-height:100%;margin-bottom:0.1in;background:transparent"><span style="font-family:arial,sans-serif">Below is the
relevant portion of my input file:</span></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">&CONTROL</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">calculation =
"scf"</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">max_seconds =
8.64000e+04</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">outdir =
"./"</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">prefix =
"espresso"</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">pseudo_dir = ......pseudopot"</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">title =
"Ag20"</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">wf_collect =
.TRUE.</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">wfcdir =
"./"</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">/</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><span style="font-family:arial,sans-serif"><br></span>
</p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">&SYSTEM</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">a
= 4.75399e+00</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">degauss
= 1.00000e-02</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">ecutrho
= 4.80000e+02</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">ecutwfc
= 6.00000e+01</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">exx_fraction
= 2.50000e-01</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">exxdiv_treatment
= "gygi-baldereschi"</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">ibrav
= 1</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">input_dft
= "HSE"</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">nat
= 6</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">nspin
= 2</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">ntyp
= 2</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">occupations
= "smearing"</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent">
<b style="font-family:arial,sans-serif">screening_parameter = 2.00000e-01</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">smearing
= "marzari-vanderbilt"</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent">
<b style="font-family:arial,sans-serif">starting_magnetization(1) = 2.00000e-01</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent">
<b style="font-family:arial,sans-serif">starting_magnetization(2) = 0.00000e+00</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">/</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><span style="font-family:arial,sans-serif"><br></span>
</p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">&ELECTRONS</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">conv_thr
= 1.00000e-06</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">electron_maxstep
= 200</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">mixing_beta
= 4.00000e-01</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">startingpot
= "atomic"</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">startingwfc
= "atomic+random"</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">/</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">K_POINTS
{automatic}</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"> <b style="font-family:arial,sans-serif">8 8 8 0 0 0</b></p><p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif"><br></b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">ATOMIC_SPECIES</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">Ag 107.86820
Ag.pbe-d-rrkjus.UPF</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">O 15.99940
O.pbe-rrkjus.UPF</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><span style="font-family:arial,sans-serif"><br></span>
</p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">ATOMIC_POSITIONS
{angstrom}</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">Ag 1.188498
1.188498 3.565493</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">Ag 3.565493
1.188498 1.188498</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">Ag 1.188498
3.565493 1.188498</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">Ag 3.565493
3.565493 3.565493</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">O 0.000000
0.000000 0.000000</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><b style="font-family:arial,sans-serif">O 2.376995
2.376995 2.376995</b></p>
<p style="margin-bottom:0in;line-height:100%;background:transparent"><span style="font-family:arial,sans-serif"><br></span>
</p>
<p style="font-weight:normal;line-height:100%;margin-bottom:0.1in;background:transparent"><span style="font-family:arial,sans-serif">Any insights or
recommendations would be greatly appreciated.</span></p>
<p style="line-height:100%;margin-bottom:0.1in;background:transparent"><span style="font-family:arial,sans-serif">Thank you for your attention.</span></p><p style="line-height:100%;margin-bottom:0.1in;background:transparent"><span style="font-family:arial,sans-serif"><br></span></p><p style="line-height:100%;margin-bottom:0.1in;background:transparent"><span style="font-family:arial,sans-serif">Regards,</span></p><p style="line-height:100%;margin-bottom:0.1in;background:transparent"><span style="font-family:arial,sans-serif">Moses<br></span></p></div></div>