ELPH WF CACHE PREFILL - Revision history

Csheldon at 13:35, 18 June 2026

2026-06-18T13:35:09Z

← Older revision		Revision as of 13:35, 18 June 2026
Line 1:		Line 1:
	{{DISPLAYTITLE\|ELPH_WF_CACHE_PREFILL}}		{{DISPLAYTITLE:ELPH_WF_CACHE_PREFILL}}
	{{TAGDEF\|ELPH_WF_CACHE_PREFILL\|logical\|.TRUE.}}		{{TAGDEF\|ELPH_WF_CACHE_PREFILL\|logical\|.TRUE.}}

Miranda.henrique at 12:54, 18 June 2026

2026-06-18T12:54:10Z

← Older revision		Revision as of 12:54, 18 June 2026
Line 3:		Line 3:

	Description: Pre-fills the wavefunction cache before the main electron-phonon loop begins.		Description: Pre-fills the wavefunction cache before the main electron-phonon loop begins.

	{{Available\|6.5.0}}		{{Available\|6.5.0}}
	----		----
Line 15:		Line 14:
	* {{TAG\|ELPH_WF_REDISTRIBUTE}}		* {{TAG\|ELPH_WF_REDISTRIBUTE}}
	* {{TAG\|ELPH_WF_COMM_OPT}}		* {{TAG\|ELPH_WF_COMM_OPT}}
	* {{TAG\|ELPH_MELS}}
	[[Category:INCAR tag]][[Category:Electron-phonon_interactions]]		[[Category:INCAR tag]][[Category:Electron-phonon_interactions]]

Miranda.henrique: Remove wf cache is full error note

2026-06-18T12:23:40Z

Remove wf cache is full error note

← Older revision		Revision as of 12:23, 18 June 2026
Line 10:		Line 10:

	Setting <code>ELPH_WF_CACHE_PREFILL = .FALSE.</code> disables pre-filling; wavefunctions are then fetched on demand during the loop. This reduces the upfront communication cost but increases total MPI traffic and is generally slower.		Setting <code>ELPH_WF_CACHE_PREFILL = .FALSE.</code> disables pre-filling; wavefunctions are then fetched on demand during the loop. This reduces the upfront communication cost but increases total MPI traffic and is generally slower.

	~~{{NB\|text=Pre-filling requires the cache to be large enough to hold all wavefunctions needed by the calculation. If VASP aborts with <code>wf cache is full</code>, increase {{TAG\|ELPH_WF_CACHE_MB}}.}}~~

	==Related tags and articles==		==Related tags and articles==

Miranda.henrique: Improve ELPH_WF_CACHE_PREFILL: fix TAGDEF/DISPLAYTITLE formatting, expand body, add ELPH_WF_CACHE_MB link, remove ELPH_TRANSPORT

2026-06-18T12:23:12Z

Improve ELPH_WF_CACHE_PREFILL: fix TAGDEF/DISPLAYTITLE formatting, expand body, add ELPH_WF_CACHE_MB link, remove ELPH_TRANSPORT

← Older revision		Revision as of 12:23, 18 June 2026
Line 1:		Line 1:
	{{DISPLAYTITLE:ELPH_WF_CACHE_PREFILL}}		{{DISPLAYTITLE\|ELPH_WF_CACHE_PREFILL}}
	{{TAGDEF\|ELPH_WF_CACHE_PREFILL\|[logical]\| .TRUE.}}		{{TAGDEF\|ELPH_WF_CACHE_PREFILL\|logical\|.TRUE.}}

			Description: Pre-fills the wavefunction cache before the main electron-phonon loop begins.

	~~Description:~~
	~~Determines whether to pre-fill the wavefunction (WF) cache before starting the calculation.~~
	{{Available\|6.5.0}}		{{Available\|6.5.0}}
	----		----

	When ~~enabled~~, the cache ~~is populated~~ in ~~advance, avoiding one~~-~~sided~~ MPI ~~communication~~ during the ~~main computation~~ loop.		When computing electron-phonon matrix elements, VASP caches wavefunctions fetched from remote MPI ranks (see {{TAG\|ELPH_WF_CACHE_MB}}). With <code>ELPH_WF_CACHE_PREFILL = .TRUE.</code> (the default), all required wavefunctions are gathered into the cache in a single communication phase before the main loop starts. This means the loop itself runs with little or no inter-rank MPI traffic.
	This ~~can significantly improve performance~~ and ~~scalability~~, ~~especially for large parallel runs~~.
			Setting <code>ELPH_WF_CACHE_PREFILL = .FALSE.</code> disables pre-filling; wavefunctions are then fetched on demand during the loop. This reduces the upfront communication cost but increases total MPI traffic and is generally slower.

			{{NB\|text=Pre-filling requires the cache to be large enough to hold all wavefunctions needed by the calculation. If VASP aborts with <code>wf cache is full</code>, increase {{TAG\|ELPH_WF_CACHE_MB}}.}}

	==Related tags and articles==		==Related tags and articles==
			* {{TAG\|ELPH_WF_CACHE_MB}}
	* {{TAG\|ELPH_WF_REDISTRIBUTE}}		* {{TAG\|ELPH_WF_REDISTRIBUTE}}
	* {{TAG\|ELPH_WF_COMM_OPT}}		* {{TAG\|ELPH_WF_COMM_OPT}}
	* {{TAG\|~~ELPH_TRANSPORT~~}}		* {{TAG\|ELPH_MELS}}
	[[Category:INCAR tag]][[Category:Electron-phonon_interactions]]		[[Category:INCAR tag]][[Category:Electron-phonon_interactions]]

Csheldon: /* Related tags and articles */

2025-10-24T15:14:49Z

Csheldon: Csheldon moved page Construction:ELPH WF CACHE PREFILL to ELPH WF CACHE PREFILL

2025-10-22T14:31:19Z

Csheldon moved page Construction:ELPH WF CACHE PREFILL to ELPH WF CACHE PREFILL

← Older revision	Revision as of 14:31, 22 October 2025
(No difference)

Csheldon at 14:31, 22 October 2025

2025-10-22T14:31:15Z

← Older revision		Revision as of 14:31, 22 October 2025
Line 13:		Line 13:
	* {{TAG\|ELPH_WF_REDISTRIBUTE}}		* {{TAG\|ELPH_WF_REDISTRIBUTE}}
	* {{TAG\|ELPH_TRANSPORT}}		* {{TAG\|ELPH_TRANSPORT}}
	~~<!--~~[[Category:INCAR tag]][[Category:Electron-phonon_interactions]]~~-->~~		[[Category:INCAR tag]][[Category:Electron-phonon_interactions]]

Miranda.henrique at 14:13, 16 October 2025

2025-10-16T14:13:19Z

← Older revision		Revision as of 14:13, 16 October 2025
Line 11:		Line 11:

	==Related tags and articles==		==Related tags and articles==
	{{TAG\|ELPH_WF_REDISTRIBUTE}},		* {{TAG\|ELPH_WF_REDISTRIBUTE}}
	{{TAG\|ELPH_TRANSPORT}}		* {{TAG\|ELPH_TRANSPORT}}
			<!--[[Category:INCAR tag]][[Category:Electron-phonon_interactions]]-->
	[[Category:INCAR tag]][[Category:Electron-phonon_interactions]]
	~~[[Category:Parallelization_options]]~~
	~~[[Category:Performance_optimization]]~~

Miranda.henrique: Created page with "{{DISPLAYTITLE:ELPH_WF_CACHE_PREFILL}} {{TAGDEF|ELPH_WF_CACHE_PREFILL|[logical]| .TRUE.}} Description: Determines whether to pre-fill the wavefunction (WF) cache before starting the calculation. {{Available|6.5.0}} ---- When enabled, the cache is populated in advance, avoiding one-sided MPI communication during the main computation loop. This can significantly improve performance and scalability, especially for large parallel runs. ==Related tags and articles==..."

2025-10-16T13:48:12Z

Created page with "{{DISPLAYTITLE:ELPH_WF_CACHE_PREFILL}} {{TAGDEF|ELPH_WF_CACHE_PREFILL|[logical]| .TRUE.}} Description: Determines whether to pre-fill the wavefunction (WF) cache before starting the calculation. {{Available|6.5.0}} ---- When enabled, the cache is populated in advance, avoiding one-sided MPI communication during the main computation loop. This can significantly improve performance and scalability, especially for large parallel runs. ==Related tags and articles==..."

New page

{{DISPLAYTITLE:ELPH_WF_CACHE_PREFILL}}
{{TAGDEF|ELPH_WF_CACHE_PREFILL|[logical]| .TRUE.}}

Description:
Determines whether to pre-fill the wavefunction (WF) cache before starting the calculation.
{{Available|6.5.0}}
----

When enabled, the cache is populated in advance, avoiding one-sided MPI communication during the main computation loop.
This can significantly improve performance and scalability, especially for large parallel runs.

==Related tags and articles==
{{TAG|ELPH_WF_REDISTRIBUTE}},
{{TAG|ELPH_TRANSPORT}}

[[Category:INCAR tag]][[Category:Electron-phonon_interactions]]
[[Category:Parallelization_options]]
[[Category:Performance_optimization]]

← Older revision		Revision as of 15:14, 24 October 2025
Line 12:		Line 12:
	==Related tags and articles==		==Related tags and articles==
	* {{TAG\|ELPH_WF_REDISTRIBUTE}}		* {{TAG\|ELPH_WF_REDISTRIBUTE}}
			* {{TAG\|ELPH_WF_COMM_OPT}}
	* {{TAG\|ELPH_TRANSPORT}}		* {{TAG\|ELPH_TRANSPORT}}
	[[Category:INCAR tag]][[Category:Electron-phonon_interactions]]		[[Category:INCAR tag]][[Category:Electron-phonon_interactions]]