I am having the same problem. Multiple times per day I have to restart X1 and it's not indexing any where near as many items as it had before I blew up the index and restarted it.
<?xml version="1.0" encoding="utf-8"?>
<CrashLog>
<User LogID="0" InstallID="{cfea1a34-0802-49ce-bb53-ba9576f5ebe1}" Email="" CountryCode="1" Company="" ChannelName="X1">
<UserDescription />
</User>
<CrashDetails CrashDate="2014-01-02 22:04:59" CrashDateInfo="Utc (Utc offset -06:00)" BuildNumber="5001bc" AppName="X1Pro" AppComponent="X1ServiceHost.exe" MiniDumpFileName="1234abcd-2f1c-0e1a-2b93-6cf263e072bd">
<Data />
<ErrorMessage>UnmanagedCodeException: Exception thrown. Message: Out Of Memory in vector::resize (size=88543950 bytes)</ErrorMessage>
<HelpLink />
<StackTrace />
<TypedValues>(Int32)HResult=-2146233088
</TypedValues>
<InnerException />
<CurrentManagedStack>LogCrash at offset 709 in file:line:column <filename unknown>:0:0
LogCrash at offset 67 in file:line:column <filename unknown>:0:0
a at offset 215 in file:line:column <filename unknown>:0:0
IX1_Idle at offset 0 in file:line:column <filename unknown>:0:0
Idle at offset 28 in file:line:column <filename unknown>:0:0
a at offset 182 in file:line:column <filename unknown>:0:0
ThreadStart_Context at offset 111 in file:line:column <filename unknown>:0:0
RunInternal at offset 167 in file:line:column <filename unknown>:0:0
Run at offset 22 in file:line:column <filename unknown>:0:0
Run at offset 65 in file:line:column <filename unknown>:0:0
ThreadStart at offset 68 in file:line:column <filename unknown>:0:0
</CurrentManagedStack>
<LastNativeException>Exception thrown. Message: Out Of Memory in vector::resize (size=88543950 bytes)</LastNativeException>
<NativeModuleInfo />
</CrashDetails>
<ComputerDetails>
<OS CodeSet="1252" OSLanguage="1033" PAEEnabled="" IsPrimaryOS="True" OperatingSystemSKU="48" OSProductSuite="256" ProductType="1" OtherTypeDescription="" MaxProcessMemorySize="8589934464">
<DetailedOSDescription>6.1.7601.65536, Service Pack 1, Win32NT</DetailedOSDescription>
<BootDevice>\Device\HarddiskVolume1</BootDevice>
<SystemDevice>\Device\HarddiskVolume2</SystemDevice>
<SystemDirectory>C:\Windows\system32</SystemDirectory>
<WindowsDirectory>C:\Windows</WindowsDirectory>
</OS>
<LastBootUpTime>5.62</LastBootUpTime>
<CPU>Pentium(R) Dual-Core CPU E6700 @ 3.20GHz - Intel64 Family 6 Model 23 Stepping 10</CPU>
<VirtualMem>Free: 10957684kb of 16704948kb</VirtualMem>
<PhysicalMem>Free: 7224984kb of 12512508kb</PhysicalMem>
<PageFileMem>Free: 3683044kb of 4194304kb</PageFileMem>
<HDDs>
<LogicalHardDrive Name="C:" Free="60264366080" Size="159934050304" />
<LogicalHardDrive Name="E:" Free="189141749760" Size="244948836352" />
</HDDs>
<OutlookVersion />
<MapiVersion />
<FirefoxVersion />
<DotNetVersions>
<DotNetVerion>2.0.50727.5420</DotNetVerion>
<DotNetVerion>3.0.30729.5420</DotNetVerion>
<DotNetVerion>3.5.30729.5420</DotNetVerion>
<DotNetVerion>4.5.50709</DotNetVerion>
<DotNetVerion>4.0.0.0</DotNetVerion>
</DotNetVersions>
</ComputerDetails>
</CrashLog>
<?xml version="1.0" encoding="utf-8"?>
<CrashLog>
<User LogID="0" InstallID="{cfea1a34-0802-49ce-bb53-ba9576f5ebe1}" Email="" CountryCode="1" Company="" ChannelName="X1">
<UserDescription />
</User>
<CrashDetails CrashDate="2014-01-02 22:04:59" CrashDateInfo="Utc (Utc offset -06:00)" BuildNumber="5001bc" AppName="X1Pro" AppComponent="X1ServiceHost.exe" MiniDumpFileName="1234abcd-2f1c-0e1a-2b93-6cf263e072bd">
<Data />
<ErrorMessage>UnmanagedCodeException: Exception thrown. Message: Out Of Memory in vector::resize (size=88543950 bytes)</ErrorMessage>
<HelpLink />
<StackTrace />
<TypedValues>(Int32)HResult=-2146233088
</TypedValues>
<InnerException />
<CurrentManagedStack>LogCrash at offset 709 in file:line:column <filename unknown>:0:0
LogCrash at offset 67 in file:line:column <filename unknown>:0:0
a at offset 215 in file:line:column <filename unknown>:0:0
IX1_Idle at offset 0 in file:line:column <filename unknown>:0:0
Idle at offset 28 in file:line:column <filename unknown>:0:0
a at offset 182 in file:line:column <filename unknown>:0:0
ThreadStart_Context at offset 111 in file:line:column <filename unknown>:0:0
RunInternal at offset 167 in file:line:column <filename unknown>:0:0
Run at offset 22 in file:line:column <filename unknown>:0:0
Run at offset 65 in file:line:column <filename unknown>:0:0
ThreadStart at offset 68 in file:line:column <filename unknown>:0:0
</CurrentManagedStack>
<LastNativeException>Exception thrown. Message: Out Of Memory in vector::resize (size=88543950 bytes)</LastNativeException>
<NativeModuleInfo />
</CrashDetails>
<ComputerDetails>
<OS CodeSet="1252" OSLanguage="1033" PAEEnabled="" IsPrimaryOS="True" OperatingSystemSKU="48" OSProductSuite="256" ProductType="1" OtherTypeDescription="" MaxProcessMemorySize="8589934464">
<DetailedOSDescription>6.1.7601.65536, Service Pack 1, Win32NT</DetailedOSDescription>
<BootDevice>\Device\HarddiskVolume1</BootDevice>
<SystemDevice>\Device\HarddiskVolume2</SystemDevice>
<SystemDirectory>C:\Windows\system32</SystemDirectory>
<WindowsDirectory>C:\Windows</WindowsDirectory>
</OS>
<LastBootUpTime>5.62</LastBootUpTime>
<CPU>Pentium(R) Dual-Core CPU E6700 @ 3.20GHz - Intel64 Family 6 Model 23 Stepping 10</CPU>
<VirtualMem>Free: 10957684kb of 16704948kb</VirtualMem>
<PhysicalMem>Free: 7224984kb of 12512508kb</PhysicalMem>
<PageFileMem>Free: 3683044kb of 4194304kb</PageFileMem>
<HDDs>
<LogicalHardDrive Name="C:" Free="60264366080" Size="159934050304" />
<LogicalHardDrive Name="E:" Free="189141749760" Size="244948836352" />
</HDDs>
<OutlookVersion />
<MapiVersion />
<FirefoxVersion />
<DotNetVersions>
<DotNetVerion>2.0.50727.5420</DotNetVerion>
<DotNetVerion>3.0.30729.5420</DotNetVerion>
<DotNetVerion>3.5.30729.5420</DotNetVerion>
<DotNetVerion>4.5.50709</DotNetVerion>
<DotNetVerion>4.0.0.0</DotNetVerion>
</DotNetVersions>
</ComputerDetails>
</CrashLog>