<?xml version="1.0" encoding="utf-8"?>
<!--Generated by DFIN XBRL Instance Document - http://www.dfinsolutions.com/ - Version R3.0 - on 04-March-2025 [11:21:28] {PM}-->
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<link:roleType roleURI="http://www.pimco.com/role/N2InvestmentObjectives" id="N2InvestmentObjectives">
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<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
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<link:roleType roleURI="http://www.pimco.com/role/N2SharePriceTable" id="N2SharePriceTable">
<link:definition>1002 - Disclosure - N-2 - [Share Price Table]</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.pimco.com/role/N2OutstandingSecurities" id="N2OutstandingSecurities">
<link:definition>1003 - Disclosure - N-2 - [Outstanding Securities]</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:linkbaseRef xlink:type="simple" xlink:href="pfi-20241231_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
<link:linkbaseRef xlink:type="simple" xlink:href="pfi-20241231_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
<link:linkbaseRef xlink:type="simple" xlink:href="pfi-20241231_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
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<import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
<import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
<import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
<import namespace="http://xbrl.sec.gov/dei/2024" schemaLocation="https://xbrl.sec.gov/dei/2024/dei-2024.xsd" />
<import namespace="http://www.xbrl.org/dtr/type/2020-01-21" schemaLocation="https://www.xbrl.org/dtr/type/2020-01-21/types.xsd" />
<import namespace="http://xbrl.sec.gov/cef/2024" schemaLocation="https://xbrl.sec.gov/cef/2024/cef-2024.xsd" />
<import namespace="http://xbrl.sec.gov/cef-pre/2024" schemaLocation="https://xbrl.sec.gov/cef/2024/cef-2024_pre.xsd" />
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</schema>
